Solid state cooler

Abstract

A cooling system includes a system heat sink and a first magnetocaloric heat transport medium. The first magnetocaloric heat transport medium is connected to the system heat sink. The first magnetocaloric heat transport medium includes a semimetal.

Description

Background Technology

[0001] This invention relates to cooling systems, and more particularly, to cooling systems for electronic applications.

[0002] Cooling systems for electronic applications take different forms depending on the characteristics of the application. Large electronic devices with lower temperature sensitivity, such as server racks, typically rely on fan arrays to push airflow over the devices. Such solutions use air at near room temperature to maintain the temperature of heat-generating devices (such as memory and processors) below 100 degrees Celsius (i.e., 373.15 Kelvin).

[0003] However, cooling systems for more temperature-sensitive electronic devices typically employ more sophisticated solutions to maintain lower temperatures. For example, quantum systems include heat-generating devices that should be kept below 2 Kelvin (2 K) for optimal function. Summary of the Invention

[0004] Some embodiments of this disclosure may take the form of a first cooling system. The first cooling system may include a magnetothermal radiator, a device magnetothermal switch, and a radiator magnetothermal switch. The device magnetothermal switch connects the heat-generating device to the magnetothermal radiator, and the radiator magnetothermal switch connects to the system radiator.

[0005] Some embodiments of this disclosure may employ a second cooling system. This second cooling system includes a magnetocaloric medium, a first set of electromagnets, and a second set of electromagnets. The magnetocaloric medium is connected to the heat-generating equipment and the system radiator. The first set of electromagnets is located in a first region adjacent to the magnetocaloric medium. The first region is adjacent to the heat-generating equipment. The second set of electromagnets is located in a second region adjacent to the magnetocaloric medium. The second region is adjacent to the system radiator.

[0006] Some embodiments of this disclosure may take the form of a third cooling system. This third cooling system includes a system heat sink and a first magnetocaloric heat transfer medium. The first magnetocaloric heat transfer medium is connected to the system heat sink. The first magnetocaloric heat transfer medium comprises a semi-metal.

[0007] Some embodiments of this disclosure can take the form of a method for cooling a heat-generating device. This method may include activating a first group of electromagnets adjacent to the magnetocaloric medium. Activating the first group of electromagnets divides the magnetocaloric medium into activated and inactive regions. Attached Figure Description

[0008] Figure 1A-1J A cooling system is depicted in an example stage of a cooling process according to an embodiment of the present disclosure, the cooling system including a magnetothermal radiator and a set of magnetothermal switches.

[0009] Figure 2The process of using a cooling system according to an embodiment of the present disclosure is described, the cooling system including a magnetothermal radiator and a set of magnetothermal switches.

[0010] Figure 3A-3P A cooling system comprising several regions of a magnetothermal heat transfer medium is depicted as an example stage of a cooling process according to an embodiment of the present disclosure.

[0011] Figure 4 The process of using a cooling system according to an embodiment of the present disclosure is described, the cooling system including a set of electromagnets that can be used to pump heat through a magnetothermal medium.

[0012] Figure 5 A magnetocaloric heat transfer medium with a heat transfer supplement applied thereon is depicted according to an embodiment of the present disclosure.

[0013] Figure 6A-6R A series of stages for forming a cooling system according to embodiments of the present disclosure are described, the cooling system including a set of electromagnets that can be used to pump heat via a magnetothermal medium.

[0014] Figure 7A-7L A series of stages for forming a cooling system according to embodiments of the present disclosure are described, the cooling system including a magnetothermal radiator and a set of magnetothermal switches. Detailed Implementation

[0015] Cooling systems for electronic applications take various forms depending on the needs of those applications. For example, a standard desktop computer operates a set of fans to blow room temperature air over heat-generating components within the computer (e.g., system processor, voltage regulator, system memory). These systems are typically sufficient to maintain the heat-generating components at temperatures above room temperature but within the system's specifications (e.g., between 50 and 90 degrees Celsius).

[0016] Some cooling systems for more sensitive electronic devices, such as quantum devices, employ more complex forms to maintain heat-generating equipment at extremely low temperatures. For example, a typical quantum computer cooling system involves supplying liquid hydrogen or helium instead of room temperature air. Some cooling systems also utilize adiabatic cooling techniques, manipulating the heat capacity of a substance to cause it to absorb heat from the heat-generating component in one location and release it back into the environment in another.

[0017] In some adiabatic systems, the cooling material is first pressurized, causing it to change from a gaseous to a liquid state. This compression reduces the cooling material's heat capacity, making it prone to releasing heat to the surrounding environment. After releasing heat, the cooling material is then transferred and depressurized, causing it to change back from a liquid to a gaseous state. This change reduces the cooling material's internal energy, thereby increasing its heat capacity. This, in turn, makes it prone to absorbing heat from the surrounding environment. If the cooling material in this gaseous state comes into contact with a heat-generating device, it will absorb heat from the device. This heat can then be transported out of the heat-generating device along with the cooling material, which can then change back to a gaseous state to release heat back into the environment. For example, some cryogenic coolers cool cryogenic electronic equipment by subjecting nitrogen, hydrogen, or helium to this process. These systems can maintain the temperature of heat-generating equipment below 2 Kelvin.

[0018] Some cryogenic coolers do not rely on the transformation of the cooling material between gaseous and liquid states, but instead utilize the magnetocaloric properties of the cooling material to generate an adiabatic effect. A material with magnetocaloric properties (sometimes referred to herein as a "magnetocaloric material") can be exposed to a magnetic field to increase its heat capacity, and then isolated from the magnetic field to decrease its heat capacity. For example, some fluids containing magnetocaloric materials can be pumped through a region containing a magnetic field, thereby increasing their heat capacity. This fluid can then be pumped into contact with a heat-generating device, causing the fluid to absorb heat from the device. Subsequently, the fluid can be pumped away from the heat-generating device and removed from the magnetic field, resulting in a decrease in the heat capacity of the magnetocaloric material. As a result, the fluid transfers the heat absorbed from the heat-generating element to the surrounding environment.

[0019] In some cooling solutions, solid magnetocaloric materials can be used instead of fluids containing magnetocaloric materials. In these solutions, the solid magnetocaloric material is typically moved, bringing it into contact with the heat-generating device within a magnetic field. The magnetic field causes an increase in the heat capacity of the magnetocaloric material, allowing it to absorb heat from the heat-generating device. The magnetocaloric material can then be removed from the heat-generating device and out of the magnetic field via a mechanical process, such as using a piston. Once outside the magnetic field, the magnetocaloric material can come into contact with a radiator, allowing it to transfer heat to the radiator.

[0020] The adiabatic cooling solutions discussed above all require some type of mechanical intervention. For example, transporting fluids (gas or liquid) typically requires a pump, while moving solid-state magnetocaloric components may require pistons or levers. Because of this mechanical intervention, these solutions are difficult to miniaturize. The mechanical systems required for these cryogenic cooling solutions involve very small moving parts that are prone to fatigue and failure. Therefore, even when these components can be operated at such a small scale, significant maintenance investment is sometimes required.

[0021] This is unfortunate because many heat-generating devices that are most likely to benefit from temperatures of 2 Kelvin or lower are very small. For example, the cooling devices discussed above that provide sufficient cooling for detector pixels, quantum devices, or logic components are typically orders of magnitude larger than the pixel, device, or component.

[0022] The size requirements needed to cool these devices to single-digit temperatures often pose a significant barrier to their use outside of academic settings. For example, the material costs required to build a cryogenic cooling system for a single quantum device may render the investment unprofitable.

[0023] Current cryogenic cooling solutions create barriers to entry that may hinder investment in temperature-sensitive devices such as quantum devices. This, in turn, slows progress in areas such as quantum technology. Until these issues are resolved, operation of temperature-sensitive devices may remain confined to academic and niche commercial environments, preventing most of society from benefiting from the potential advantages these devices could offer.

[0024] One potential solution to the above problem is to use a solid-state magnetocaloric cooler with no moving parts. For example, a heat-generating device like a quantum sensor could be attached to a magnetocaloric material sample, which in turn could be attached to a heat sink. Theoretically, by placing the magnetocaloric material sample in a magnetic field, the sample's thermal capacity increases, allowing it to absorb heat from the heat-generating device. Furthermore, also theoretically, by isolating the magnetocaloric material sample from the magnetic field, the sample's thermal capacity decreases, allowing it to transfer heat to the heat sink.

[0025] Unfortunately, operating such solid-state magnetocaloric coolers also presents several challenges. First, the magnetocaloric effect of most materials is very small. In other words, even when these materials are placed in an extremely strong magnetic field, the increase in their heat capacity and thermal conductivity is negligible. Therefore, the cooling capacity of such systems is very limited and unsuitable for temperature-sensitive electronic devices. That is, to provide sufficient heat capacity difference, it may be necessary to use a large amount of magnetocaloric material to build the system, which in turn requires an extremely strong magnetic field. Such cooling systems are not only expensive to build and operate, but may still only provide enough cooling to allow for temporary operation of temperature-sensitive devices.

[0026] Furthermore, as mentioned earlier, such solid-state magnetocaloric coolers may require strong magnetic fields. Unfortunately, these fields can not only interact with the magnetocaloric sample but also interfere with the operation of the heat-generating device the system is attempting to cool. For example, quantum devices are typically very sensitive to magnetic fields, in addition to being highly sensitive to temperature. Therefore, the magnetic field strength required for certain magnetocaloric cooler designs makes them unsuitable for the applications in which they are developed.

[0027] To address the aforementioned problems, some embodiments of this disclosure utilize a magnetothermal cooler with a low-intensity magnetic field and a magnetothermal heat transfer medium that provides high cooling performance. These advantages are achieved through several innovative features in the embodiments of this disclosure.

[0028] First, some embodiments of this disclosure utilize a heat transfer medium composed of a half-metal (i.e., one or more solid media designed to transfer heat from a heat-generating device to a radiator). For example, topological half-metals with small Fermi surfaces, high electron mobility, and large shielding lengths can exhibit large magnetocaloric effects even when a relatively small local magnetic field is applied to the half-metal. Therefore, by utilizing a heat transfer medium composed of, for example, crystalline tantalum arsenide (TaAs), crystalline zirconium pentatelluride (ZrTe5), or crystalline niobium phosphide (NbP), sufficient magnetocaloric effect can be achieved to facilitate significant heat transfer from the heat-generating device without exposing the heat-generating device to significant magnetic flux.

[0029] Some embodiments of this disclosure also utilize multiple localized magnetic fields to generate a magnetocaloric effect in the heat transfer medium, rather than a single large magnetic field. For example, this can be achieved by using a group or series of small electromagnets to generate localized magnetic fields. These electromagnets can take the form of solenoids, patterned wires, flat patterned coils, or other forms, as will be discussed in more detail below.

[0030] For example, some embodiments of this disclosure may include a heat transfer medium in the form of an intermediate magnetocaloric radiator (sometimes simply referred to herein as a "magnetothermal radiator"). The intermediate magnetocaloric radiator is referred to herein as an "intermediate" magnetocaloric radiator because it is a magnetocaloric component of a cooling system designed to act as a radiator between a heat-generating device and a system radiator operating in a heat pump cycle. The intermediate magnetocaloric radiator can be connected to the heat-generating device via an elongated magnetocaloric component. As will be explained below, this elongated magnetocaloric component can operate as a steady-state thermal switch, capable of turning heat transfer between other components on and off. Therefore, this component is referred to herein as a "magnetothermal switch."

[0031] The length of a magnetocaloric switch in the dimension between the heat-generating device and the intermediate magnetocaloric radiator can be significantly greater than its thickness in other dimensions. This not only allows a relatively weak magnetic field to produce a significant magnetocaloric effect in the magnetocaloric switch, but also keeps the overall heat capacity of the magnetocaloric switch relatively small. In other words, exposing the magnetocaloric switch to a magnetic field increases its thermal conductivity, allowing heat to pass through. However, due to the size of the switch, exposing it to a magnetic field does not enable it to contain a large amount of heat.

[0032] Therefore, individual electromagnets can be placed very close to the intermediate magnetothermal radiator and the magnetothermal switch (e.g., within one millimeter). Activating the electromagnet near the intermediate magnetothermal radiator exposes it to a magnetic field, thereby increasing its heat capacity. Thus, when both electromagnets for the magnetothermal switch and the intermediate magnetothermal radiator are activated, heat can flow from the heat-generating device into the intermediate magnetothermal radiator through the magnetothermal switch. Furthermore, if the electromagnet located near the magnetothermal switch is subsequently deactivated, the thermal conductivity of the magnetothermal switch decreases, preventing heat from returning from the intermediate magnetothermal radiator to the heat-generating device.

[0033] Because the electromagnets of the magnetocalor and the magnetocalor switch can operate independently, each electromagnet can be designed to be smaller. This can offset the influence of either electromagnet on the heat-generating equipment. Furthermore, since the electromagnet adjacent to the magnetocalor switch can be particularly small, its influence on the heat-generating equipment may be even more limited. Finally, since the electromagnet adjacent to the magnetocalor switch can be isolated from the heat-generating equipment by the magnetocalor switch, its influence on the heat-generating equipment may also be even more limited.

[0034] Finally, once the heat from the heat-generating equipment is effectively captured in the magnetothermal radiator, it can be transferred to the system radiator by isolating the magnetothermal radiator from the magnetic field. This reduces the heat capacity of the magnetothermal radiator, allowing heat to be transferred from it to the system radiator. In some embodiments, the magnetothermal radiator can be directly connected to the system radiator, allowing direct heat transfer. In other embodiments, the magnetothermal radiator can be indirectly connected to the system radiator. For example, a second magnetothermal switch can connect the magnetothermal radiator to the system radiator. This second magnetothermal switch can be activated by a third electromagnet. This activation is similar to the activation of the first magnetothermal switch, allowing heat to be transferred from the magnetothermal radiator to the system radiator through the second magnetothermal switch without significantly increasing the heat capacity of the second magnetothermal switch. Furthermore, once heat is transferred to the magnetothermal radiator, the second magnetothermal switch can be isolated from the magnetic field, effectively preventing heat from the system radiator from flowing back to the magnetothermal radiator.

[0035] It is worth noting that some embodiments of the designs discussed above can use topological half-metals for magnetocaloric heat sinks and magnetocaloric switches. In some such embodiments, all magnetocaloric materials can be composed of the same half-metal, while in other embodiments, different components can be composed of different half-metals. For example, in some embodiments, the magnetocaloric heat sink, the first magnetocaloric switch, and the second magnetocaloric switch can all be composed of NbP. In other embodiments, the magnetocaloric heat sink can be composed of NbP, while the magnetocaloric switch can be composed of TaAs.

[0036] Some embodiments of this disclosure also utilize multiple localized magnetic fields to manipulate the magnetocaloric heat transfer medium, using it as a heat pump. For example, the heat transfer medium can be in the form of a magnetocaloric material connected to a heat-generating device and a system radiator. The heat transfer medium can be adjacent to a set of electromagnets that are independently addressable and span the distance between the heat-generating device and the system radiator. Therefore, these electromagnets effectively divide the magnetocaloric heat transfer medium into a set of regions that can be exposed to the electric field independently of other regions of the heat transfer medium. In other words, the electromagnets can be used to change the thermal conductivity and heat capacity of one or more regions of the heat transfer medium without changing the thermal conductivity and heat capacity of other regions of the heat transfer medium.

[0037] This allows the magnetocaloric heat transfer medium to function as a heat pump without the mechanical intervention typically required to achieve heat pump functionality. For example, an electromagnet adjacent to the region of the heat transfer medium closest to the heat-generating device can be activated. This increases the thermal conductivity and heat capacity of that region, allowing heat to be transferred from the heat-generating device to the heat transfer medium. An electromagnet adjacent to the next region of the heat transfer medium can then be activated, allowing heat to be transferred from the first region to the second. The electromagnet adjacent to the first region can then be deactivated, causing any remaining heat in the first region to be transferred to the second. This process can be repeated across all regions of the heat transfer medium until the heat is pumped all the way to the system radiator. Therefore, a magnetocaloric heat transfer medium following this operating mode can be referred to herein as a magnetocaloric heat pump.

[0038] In some embodiments, the magnetothermal heat pump may be constructed from a topological semimetal. As described above, forming a magnetothermal heat pump from a topological semimetal can significantly enhance the magnetothermal response of the heat transfer material to a changing magnetic field. In some embodiments, this can improve the performance of the heat pump.

[0039] It is worth noting that portions of this disclosure sometimes refer to a component being connected to another component. Unless otherwise stated, “connected to another component” herein should be interpreted as being directly or indirectly connected to that component. As described herein, when a first component is directly connected to a second component, the two components are in physical contact with each other or only in contact with a negligible gap. For example, a heat-generating component may be described as being directly connected to a radiator even if a microscopic air layer exists between most of the surface area of ​​the connection. Similarly, if only a negligible thin layer exists between two conductive contacts to facilitate their adhesion to each other, and this thin layer does not affect their interaction in any other way, then the two conductive contacts may be described as being directly connected to each other.

[0040] On the other hand, when the first component is indirectly connected to the second component, the two components may be connected only through physical contact of the intermediate component. For example, if the heat-generating component is directly connected to a magnetorheological switch, which is directly connected to an intermediate magnetorheological radiator, and then the intermediate magnetorheological radiator is directly connected to a second magnetorheological switch, which in turn is directly connected to the system radiator, then the heat-generating component can be described as being indirectly connected to the system radiator.

[0041] For clarity, the connections between the various components in this disclosure can be described in relation to each other. One example may be that the first component is connected to the second component closer to it than to the third component (i.e., compared to the third component). Recalling the previous example, the heat-generating component may be directly connected to a magnetothermal switch, which is directly connected to an intermediate magnetothermal radiator, which in turn is directly connected to a second magnetothermal switch. In this example, both the intermediate magnetothermal radiator and the second magnetothermal switch are referred to as being indirectly connected to the heat-generating component. Furthermore, the intermediate magnetothermal radiator will be described as being connected to the heat-generating component closer to it than to the second magnetothermal switch, because the connection between the intermediate magnetothermal radiator and the heat-generating component is more compact than the connection between the second magnetothermal switch and the heat-generating component.

[0042] Finally, the discussion of embodiments of this disclosure may use terms such as thermal conductivity, thermal conductance, and thermal capacity. As used herein, thermal conductivity refers to the ability of heat to radiate through the material of a component (e.g., connected molecules), while thermal conductance refers to the ability of heat to radiate through the component. Therefore, the term "thermal conductivity" should be interpreted as a property of the material itself, while thermal conductance should be interpreted as describing the overall properties of the component. For example, the thermal conductance of a niobium phosphide magnetocaloric switch depends not only on the current thermal conductivity of the niobium phosphide in the switch but also on the shape of the switch.

[0043] More specifically, under the same environmental conditions (e.g., temperature and magnetic flux exposure), niobium phosphide in a long, thin magnetocaloric switch has the same thermal conductivity as niobium phosphide in a short, wide magnetocaloric switch. However, due to its long and thin shape, the thermal conductivity of the long, thin magnetocaloric switch will be lower than that of the short, wide magnetocaloric switch. Furthermore, since the thermal conductivity of the assembly is based on the thermal conductivity of the material within the assembly, the thermal conductivity of the two magnetocaloric switches can be modulated by exposing the niobium phosphide within these switches to a magnetic field.

[0044] Finally, the term "heat capacity" as used in this article can refer to the heat capacity of a component or the specific heat capacity of the materials within that component. The heat capacity of a component refers to the amount of thermal energy it can hold under specific environmental conditions. The specific heat capacity of a material can be understood as the ability of the material's molecules to hold thermal energy, regardless of the shape of the component formed by these molecules.

[0045] For the purposes of this disclosure, the heat capacity of a component can be interpreted as a factor of the component's mass and the specific heat capacity of the materials within the component. For example, niobium phosphide may have a relatively high specific heat capacity when exposed to a magnetic field, and a relatively low specific heat capacity when isolated from the magnetic field. However, a heavier component (e.g., a magnetocaloric radiator) may have a much larger heat capacity than a lighter component (e.g., a magnetocaloric switch), even if the specific heat capacity of the materials (e.g., niobium phosphide) within these components is the same. Furthermore, since the heat capacity of a component is a factor of the specific heat capacity of the materials within the component, the heat capacity of the component can be adjusted by influencing the specific heat capacity of the component materials. It is for this reason that the heat capacity of a magnetocaloric radiator can be adjusted by exposing niobium phosphide within the magnetocaloric radiator to a magnetic field.

[0046] The above discussion of the embodiments and advantages of this disclosure can be better understood by referring to the accompanying drawings.

[0047] For example, Figure 1A-1J A cooling system 100 is depicted in an example phase of a cooling process according to an embodiment of the present disclosure. The cooling system includes a magnetothermal radiator 102 and a set of magnetothermal switches 104 and 106. It should be noted that... Figure 1A-1J This is intended only to provide an abstract representation of the cooling system for ease of understanding.

[0048] Magnetothermal radiator 102 and magnetothermal switches 104 and 106 are used to thermally connect the heat-generating device 108 to the system radiator 110. Therefore, the magnetothermal radiator 102 and magnetothermal switches 104 and 106 can be collectively referred to as the heat transfer medium of the cooling system 100. Since magnetothermal switch 104 is directly connected to the heat-generating device 108, it can be referred to herein as the "device magnetothermal switch". Similarly, since magnetothermal switch 106 is directly connected to the system radiator 110, it can be referred to as the "radiator magnetothermal switch".

[0049] The heat-generating device 108 can take the form of, for example, a quantum sensor or other quantum device, detector pixels, logic devices (e.g., on a processor chip), or devices used for infrared imaging, metrology, or precision chemistry. The system heat sink 110 can take the form of, for example, a large mass of conductive material, a series of heat sinks, or a heat bath.

[0050] The cooling system 100 also includes electromagnets 112, 114, and 116. Electromagnet 112 is positioned near the magnetothermal radiator 102, electromagnet 114 near the magnetothermal switch 104, and electromagnet 116 near the magnetothermal switch 106. Each of electromagnets 112-116 is independently addressable, meaning that each can be activated individually without activating the other electromagnets. Furthermore, the magnetic field strength generated by each of electromagnets 112-116 is sufficient to produce a magnetothermal effect on the heat transfer medium adjacent to it, but will not produce a strong magnetothermal effect on the heat transfer medium not adjacent to it.

[0051] Therefore, as used in the purposes of this disclosure, "proximity" of an electromagnet to a heat transfer medium should be interpreted as being placed close enough to the heat transfer medium to produce a significant magnetocaloric effect when the electromagnet is activated (i.e., when the electromagnet exposes the heat transfer medium to a magnetic field). This distance can range, for example, from a few nanometers in some applications where a microcoil is integrated with or wound around a magnetocaloric switch; while in large coolers with larger solenoids, the distance can be from a few centimeters. Depending on the specific application, a magnetocaloric effect can be considered "significant" when it results in, for example, an increase in thermal conductivity of 300% (e.g., from 5 W / mK to 20 W / mK) or an increase in specific heat capacity of 700% (e.g., from 0.005 J / cm³·K to 0.04 J / cm³·K).

[0052] Similarly, the "non-adjacent" nature of an electromagnet to a heat transfer medium should be understood as meaning that when the electromagnet is activated, its placement distance from the heat transfer medium is insufficient to produce a significant magnetocaloric effect on that medium.

[0053] For ease of understanding, electromagnets 112–116 are depicted as simple coils, but they can take various forms depending on the application in which the cooling system 100 is integrated. For example, electromagnets 112–115 can take the form of solenoids placed near their respective components, solenoids wound around their respective components (e.g., the coil of electromagnet 114 can be wound around magnetothermal switch 104), patterned wires, or planar patterned coils. In some embodiments, each of electromagnets 112–116 may actually represent multiple electromagnets that can be activated together to expose their corresponding components to electromagnetic flux.

[0054] The magnetocalor radiator 102 and magnetocalor switches 104 and 106 are made of a magnetocaloric material such as a topological semimetal. Therefore, when any of the electromagnets 112-116 is activated, the associated heat transfer medium is exposed to the magnetic field, and the thermal conductivity and thermal capacity of the heat transfer medium increase. For example, if electromagnet 114 is activated, magnetocalor switch 104 will be exposed to the magnetic field, resulting in an increase in the thermal conductivity and thermal capacity of magnetocalor switch 104.

[0055] In some embodiments, the magnetocaloric radiator 102 and the magnetocaloric switches 104 and 106 may be made of the same magnetocaloric material. For example, all three may be made of niobium phosphide. In other embodiments, different materials may be used to manufacture different heat transfer media. For example, in some embodiments, the magnetocaloric radiator 102 may be made of niobium phosphide, the magnetocaloric switch 104 may be made of tantalum arsenide, and the magnetocaloric switch 106 may be made of zirconium pentatellite.

[0056] Although Figure 1A-1J Intended as an abstract representation, the approximate relative dimensions of the components illustrate the advantages of the cooling system 100 design. For example, the magnetothermal radiator 102 is depicted as larger and thicker than the magnetothermal switches 104 and 106, which are depicted as elongated shapes. The elongated shapes of switches 104 and 106 reduce the overall heat capacity and thermal conductivity of the components. Therefore, for example, even if the magnetothermal switches 104 and 102 are made of the same material with the same thermal conductivity and specific heat capacity, the magnetothermal radiator 102 will still have greater thermal conductivity and heat capacity than the magnetothermal switch 104.

[0057] Due to the characteristics of the cooling system 100 described above, the cooling system 100 can be used as a solid-state cooling system to solve many of the problems discussed above in this disclosure. For example, as Figure 1A As shown, electromagnets 112-116 were not activated, which is... Figure 1A The electromagnets 112-116 are not depicted in bold or dark ink. Therefore, the magnetothermal radiator 102 and the magnetothermal switches 104 and 106 are not exposed to the magnetic field.

[0058] Further reference Figure 1A The heat-generating device 108 is operating, and its temperature is rising. This is represented by the density of dots filling the shape of the heat-generating device 108. Similarly, since the magnetocaloric radiator 102 is not exposed to a magnetic field, it does not experience the magnetocaloric effect, and therefore its thermal conductivity and heat capacity are not enhanced. Therefore, in Figure 1A In this case, the magnetic heat sink 102 does not absorb heat from its surrounding environment.

[0059] However, in Figure 1B In this configuration, the electromagnet 112 is activated, exposing the magnetocaloric radiator 102 to a magnetic field. This magnetic field generates a magnetocaloric effect in the radiator 102, increasing its heat capacity and thermal conductivity. Therefore, the magnetocaloric radiator 102 is in a state where it can absorb heat from the surrounding environment. Figure 1B The dot density of the shape of the magnetic heat sink 102 is relatively high. Figure 1A The decrease is visually demonstrated by showing that the value has been reduced.

[0060] exist Figure 1B In this case, electromagnet 114 is not activated. Therefore, magnetothermal switch 104 is not exposed to the magnetic field, and its thermal conductivity does not increase. For this reason, although Figure 1B The magnetothermal radiator 102 is in a state where it can absorb heat from the heat-generating device 108, but the heat generated by the heat-generating device 108 still cannot be transferred to the magnetothermal radiator 102.

[0061] exist Figure 1CIn this configuration, both electromagnets 112 and 114 are activated, exposing both the magnetothermal radiator 102 and the magnetothermal switch 104 to the magnetic field. This increases the thermal conductivity of the magnetothermal switch 104, allowing heat to diffuse from the heat-generating device 108 through the magnetothermal switch 104 to the magnetothermal radiator 102. This diffusion is represented by horizontal lines filling the shape of the magnetothermal switch 104.

[0062] Figure 1D This further illustrates the heat diffusion, in which the heat-generating device 108 is cooled by a large amount of heat diffusing from the heat-generating device 108 to the magnetothermal radiator 102. This is represented by the low-density points filling the heat-generating device 108 and the high-density points filling the magnetothermal radiator 102.

[0063] exist Figure 1E In this configuration, the electromagnet 114 has been deactivated. This reduces the thermal conductivity of the magnetothermal switch 104, preventing heat from diffusing in either direction between the heat-generating device 108 and the magnetothermal radiator 102. In other words, the heat previously transferred from the heat-generating device 108 to the magnetothermal radiator 102 is now effectively trapped within the magnetothermal radiator 102.

[0064] exist Figure 1F In this process, electromagnet 112 has also been deactivated. This has caused the heat capacity of magnetothermal radiator 102 to decrease. Figure 1A The original level shown. This allows excess heat energy to be contained in the magnetothermal radiator 102, putting the magnetothermal radiator 102 in a state where it can transfer heat to the surrounding environment. In fact, the magnetothermal radiator 102 will heat up. This process begins at... Figure 1F This is reflected in the increased point density of the magnetic heat sink 102.

[0065] exist Figure 1G In the illustration, the magnetothermal radiator 102 continuously heats up due to excess internal heat. This is illustrated by depicting the magnetothermal radiator 102 as completely black. It is noteworthy that the continuous operation of the heat-generating device 108 has caused its temperature to begin to rise, which is evident in... Figure 1G The decrease in density of the filling heat-generating equipment 108 is represented by a slight reduction in the point density.

[0066] exist Figure 1H In this configuration, electromagnet 116 is activated. This exposes magnetothermal switch 106 to a magnetic field, thereby increasing its thermal conductivity. This allows heat to diffuse from magnetothermal radiator 102 to system radiator 110. Since magnetothermal radiator 102 contains excess thermal energy, it begins to transfer thermal energy to system radiator 110. Figure 1H This is illustrated by the slightly reduced point density of the magnetothermal radiator 102 and the horizontal line in the magnetothermal switch 106. In a typical embodiment, the effective thermal mass of the system radiator 110 will be significantly greater than the rest of the cooling system 100. Therefore, Figure 1HThe total thermal energy within the system radiator 110 (not shown) changes significantly.

[0067] exist Figure 1I In the middle, the magnetic heat sink 102 has transferred enough heat to the system heat sink 110 for return. Figure 1A The original thermal energy level is shown. This may occur, for example, when the temperatures of the magnetothermal radiator 102 and the system radiator 110 reach equilibrium. In some embodiments, the cooling system 100 is able to detect the temperature of 102 and identify it as having returned to its original state even if the temperatures of the magnetothermal radiator 102 and the system radiator 110 have not yet reached equilibrium.

[0068] exist Figure 1J In this process, the electromagnet 116 has been deactivated, resulting in the magnetothermal switch 106 being isolated from the magnetic field. Furthermore, the continuous operation of the heat-generating device 108 causes its temperature to rise further. Figure 1J This is manifested as an increase in the point density of the heat-generating equipment 108. Therefore, Figure 1J The cooling system 100 was shown returning to Figure 1A The state shown. Thus, the cooling system 100 can now be used again. Figures 1B to 1I Perform the same operation as shown in the diagram.

[0069] It is worth noting that the cooling system 100 is described as including one magnetothermal radiator and two magnetothermal switches. However, in some embodiments not shown, additional magnetothermal radiators may be used in series or parallel. For example, the magnetothermal radiator 102 may not be connected to the magnetothermal switch 106, but instead be directly connected to a third magnetothermal switch. This third magnetothermal switch may be directly connected to the second magnetothermal radiator, which in turn may be directly connected to the magnetothermal switch 106. Therefore, the system radiator 110 is still indirectly connected to the magnetothermal radiator 102. However, the system radiator 110 is no longer indirectly connected to the magnetothermal radiator 102 solely through the magnetothermal switch 106 (e.g., Figure 1A-1J (as shown), but is indirectly connected to the magnetic heat sink 102 through a third magnetic heat switch, a second magnetic heat sink, and magnetic heat switch 106.

[0070] For ease of understanding, Figure 2 An example process using a cooling system similar to cooling system 100 is shown, including a magnetothermal radiator and a set of magnetothermal switches. Method 200 begins at block 202, where the magnetothermal radiator is exposed to a magnetic field. This can be similar to... Figure 1BThe cooling system 100 shown is in a phase. For example, if the cooling system (or the computer operating the cooling system) detects that the heat-generating equipment that the cooling system is intended to cool has reached a threshold temperature, block 202 can be executed. In some use cases, method 200 can be configured to be executed periodically (e.g., as part of a continuous cooling cycle), in which case block 202 can be executed regardless of temperature measurement.

[0071] Method 200 continues in box 204, wherein the device's magnetothermal switch is exposed to a magnetic field. (As described above regarding...) Figure 1A-1J The magnetic thermal switch discussed can be a magnetic thermal switch directly connected to the heat-generating equipment. Therefore, box 204 can be similar to... Figure 1C This allows heat to be transferred from the heat-generating equipment to the magnetic heat sink via a magnetic thermal switch.

[0072] Method 200 continues in box 206, where a target temperature in the heat-generating device is detected. Typically, this box takes the form of detecting that the heat-generating device has cooled to a sufficiently low temperature. After detection, method 200 proceeds to box 208, where the device's magnetothermal switch is isolated from the magnetic field. This prevents heat transfer between the heat-generating device and the magnetothermal radiator. Box 208 may be similar to... Figure 1E It should be noted that in some embodiments of this disclosure, the temperature detection in block 206 may be omitted. In this case, the method will enter block 208 after a different triggering event to isolate the magnetothermal switch. For example, in some embodiments, method 200 may be configured to enter block 206 from block 204 after a predetermined amount of time.

[0073] Method 200 continues in box 210, wherein the radiator magnetothermal switch is exposed to a magnetic field. (See also: Regarding...) Figure 1A-1J The aforementioned magnetothermal switch for the radiator is a switch directly connected to the system radiator. Therefore, block 210 enables heat transfer between the magnetothermal radiator and the system radiator. Block 210 can be analogous to the electromagnet 116 that activates the cooling system 100.

[0074] Method 200 continues in block 212, wherein the magnetothermal radiator is isolated from the magnetic field. This can significantly reduce the heat capacity of the magnetothermal radiator, causing it to tend to release heat into the surrounding environment (e.g., through the radiator's magnetothermal switch to the system radiator).

[0075] It is worth noting that the above text Figure 1HThis is shown to occur only after the magnetothermal radiator (i.e., magnetothermal radiator 102) is isolated from the electric field (i.e., after the electromagnet 112 is deactivated). However, some embodiments of method 200 and cooling system 100 may isolate the magnetothermal radiator after the device's magnetothermal switch is exposed. Similarly, some embodiments of method 200 may include isolating the magnetothermal radiator before the device's magnetothermal switch is exposed (i.e., performing block 212 before block 210).

[0076] Method 200 continues in block 214, wherein the radiator magnetothermal switch is isolated from the magnetic field. This can be performed, for example, after detecting that the magnetothermal radiator has cooled to a target temperature, or after the radiator magnetothermal switch has been exposed to the magnetic field for a set period of time. Block 214 allows the cooling system to resemble... Figure 1A and Figure 1J The cooling system 100 is used, and method 200 can be terminated. It is worth noting that method 200 can be executed cyclically, periodically, or when a target temperature of the heat-generating equipment is detected.

[0077] As described above, some embodiments of this disclosure can also solve some of the aforementioned problems by utilizing multiple local magnetic fields to operate the magnetothermal heat transfer medium as a heat pump. (See reference...) Figures 3A to 3P This allows for a better understanding of the design.

[0078] Figure 3A-3P A cooling system 300 is depicted, comprising a magnetocaloric heat transfer medium 302 (also referred to as "magnetothermal medium 302"). The magnetocaloric medium 302 is in the form of a solid component of a magnetocaloric material, such as a topological half-metal. As shown, seven electromagnets 304A, 304B, 304C, 304D, 304E, 304F, and 304G have been placed near the magnetocaloric medium 302. Specifically, each of the electromagnets 304A-304G has been placed near a corresponding portion of the magnetocaloric medium 302, namely portions 306A, 306B, 306C, 306D, 306E, 306F, and 306G. Thus, for example, activating electromagnet 304A will expose portion 306A of the magnetocaloric medium 302 to a magnetic field of sufficient strength to generate a magnetocaloric effect in portion 306A.

[0079] Similar to Figure 1A-1J Electromagnets 112-116 and 304A-304G can be activated independently, allowing each of portions 306A-306G to be individually exposed to the electric field. Therefore, the magnetocaloric medium 302 is actually a single component. Although the division between portions 306A-306G is not a physical division between actual components, they can be regarded as independent magnetocaloric parts during the operation of the cooling system 300.

[0080] and Figure 1A-1JSimilar to electromagnets 112-116, for ease of understanding, electromagnets 304A-304G are depicted as simple coils, but they can take various forms depending on the application scenario in which the cooling system 300 is integrated. For example, electromagnets 304A-304G can take the form of a solenoid placed near their respective portions, a solenoid wound around their respective portions, a patterned wire (e.g., electromagnet 304C can take the form of a patterned wire formed on a substrate below portion 306C), or a flat patterned coil. In some embodiments, each of electromagnets 304A-304G can actually represent multiple electromagnets that can be activated together to expose their respective portions to electromagnetic flux.

[0081] The magnetocaloric medium 302 is connected to the heat-generating device 308 and the system radiator 310. As shown, a thermal resistance component 312 is located between the magnetocaloric medium 302 and the heat-generating device 308. This may help prevent heat from being transferred back from the magnetocaloric medium 302 to the heat-generating device 308. The form of the thermal resistance component can vary depending on the application and design of the cooling system 300. For example, in some embodiments, the thermal resistance component 312 may take the form of a thin layer, such as a dielectric layer, formed on either (or both) the magnetocaloric medium 302 and the heat-generating device 308. In some embodiments, the thermal resistance component 312 may actually take the form of a magnetocaloric material and may have a shape factor similar to that of a magnetocaloric switch 104. In these embodiments, the thermal resistance component 312 may even be paired with an electromagnet placed nearby.

[0082] As previously mentioned, the cooling system 300 can operate as a magnetothermal heat pump by independently activating electromagnets 304A–304G to effectively divide the magnetothermal medium 302 into different regions exhibiting different thermal conductivities and heat capacities. Figure 3B As shown in –3P, these regions may consist of one or more portions 306A–306G of the magnetocaloric medium 302.

[0083] For example, Figure 3B A cooling system 300 is shown after the electromagnets 304A–304C are activated, exposing portions 306A–306C to a magnetic field (or three local magnetic fields, depending on the specific implementation). This increases the thermal conductivity and heat capacity of portions 306A–306C. This effectively forms two regions of the magnetocaloric medium 302: region 314A and region 314B. Since region 314A consists of portions 306A–306C, both exposed to the magnetic field, it is in a state where it can absorb heat from the surrounding environment. This change is represented by a decrease in the point density filling portions 306A–306C.

[0084] Region 314A is exposed to the magnetic field, therefore region 314 can be referred to as the "active" region. On the other hand, region 314B is not exposed to the magnetic field, therefore region 314B can be referred to as the "inactive" region. Furthermore, since region 306D is the next downstream portion of the active region (region 314A) (i.e., towards the system radiator 310), it can be referred to herein as the leading inactive portion. Finally, since region 306A is the upstream portion of the active region (i.e., towards the heat-generating device 308), it can be referred to herein as the trailing active portion.

[0085] The result of this change is as follows: Figure 3C As shown, heat has diffused from the heat-generating device 308 to portions 306A–306C of the magnetothermal medium 302. This diffusion occurs through the thermal resistance component 312. This may be partly attributed to the thickness of the thermodynamic resistance component 312, the composition of the thermal resistance component 312, and the amount of excess heat capacity in portions 306A–306C.

[0086] Due to heat dissipation, the heat-generating device 308 has cooled significantly, which is... Figure 3C This is reflected in the reduced point density of the heat-generating device 308. Furthermore, because the heat capacity of sections 306A–306C has been largely filled with diffused heat, therefore... Figure 3C The point density of the 306A–306C portion has increased.

[0087] Figure 3D The next stage of cooling the heat-generating device 308 using the cooling system 300 is depicted. Specifically, electromagnet 304A has been deactivated, while electromagnet 304D has been activated. This has isolated part 306A from the magnetic field that previously increased its heat capacity, and exposed the previously inactive leading part 306D to the magnetic field that increased its heat capacity.

[0088] This change effectively creates three regions of the magnetocaloric medium 302: region 316A, region 316B, and region 316C. Regions 316A and 316C are similar in that they are not exposed to the magnetic field and are therefore inactive regions. Region 316B is exposed to the magnetic field and is therefore an active region. Region 316B can be considered as region 314A having moved towards the system heat sink 310. As will be described below, this movement will also tend to pump heat previously in region 314A to region 316B.

[0089] Isolating a portion of 306A from the magnetic field results in that portion of 306A containing excess heat energy. This change occurs in... Figure 3DThis manifests as an increase in the point density of the filling portion 306A. Since the thermal resistance component 312 is located between the heat-generating device 308 and portion 306A, excess heat will be difficult to return to the heat-generating device 308. Instead, excess heat may diffuse into region 316B of the magnetocaloric medium 302.

[0090] Exposing a portion of 306D to a magnetic field results in some of the 306D having excess heat capacity. This change occurs in... Figure 3D This manifests as a decrease in the point density of the filling portion 306D. This change allows portion 304D of the magnetocaloric medium 302 to absorb thermal energy from its environment (e.g., portions 306B and 306C). This also allows excess thermal energy from portion 306A to diffuse into region 316B.

[0091] This heat diffusion effect is as follows Figure 3E As shown. In Figure 3E In this process, excess heat from portion 306A has diffused into the various parts of region 316B. Furthermore, heat has reached equilibrium among the different parts of region 316B. This is reflected in the increased point density in portion 306A and the increase in point density in portion 306E to the same level as portions 306C and 306D. In other words, as... Figure 3E As shown, the heat initially transferred from the heat-generating device 308 to region 314A has been pumped into region 316B by manipulating the electromagnets 304A-304D.

[0092] Figure 3F The next stage of cooling the heat-generating device 308 using the cooling system 300 is depicted. Specifically, electromagnet 304B has been deactivated, while electromagnet 304E has been activated. This produces a [comparison / reaction] with [other features]. Figure 3D The activation and deactivation in this process have similar results. Specifically, part 306B is now isolated from the magnetic field, similar to part 306A, and contains excess thermal energy. Part 306B is in a state of dissipating heat to the surrounding environment. Part 306E is now exposed to the magnetic field, similar to parts 306C and 306D, and is in a state of absorbing heat from the surrounding environment.

[0093] This effectively divides the magnetocaloric medium 302 into three regions: region 318A, region 318B, and region 318C. (Continued) Figure 3D In this pattern, region 318B can be considered as region 316B having moved towards the system radiator 310. This will again transfer the heat extracted from the heat-generating device 308 towards the system radiator 310. Specifically, heat will diffuse from sections 306C and 306D to section 306E, while excess heat in section 306B will diffuse into region 318B.

[0094] This effect of heat diffusion is as follows Figure 3GAs shown. In other words, as Figure 3E As shown, the heat initially transferred from the heat-generating device 308 to region 314A has been pumped into region 316B and is now entering region 318B, all of which is achieved by manipulating electromagnets 304A–304D.

[0095] Figure 3H The next stage of cooling the heat-generating device 308 using the cooling system 300 is depicted. Continuing the pattern of the previous figures, the previous leading portion (part 306F) has been exposed to the magnetic field, while the previous trailing active portion (part 306C) has been isolated from the magnetic field. This effectively divides the magnetothermal medium 302 into inactive regions 320A, 320C and active region 320B.

[0096] It is worth noting that, Figure 3H The increased density of the points filling the heat-generating device 308 is also shown. This may be due to... Figures 3B to 3H This is caused by the operation of heat-generating equipment 308 during the operation of the heat pump.

[0097] Figure 3I Show Figure 3H The effect of the cooling phase. Specifically, excess heat has diffused from part 306C into region 320B, and the heat has reached equilibrium between the various parts of region 320B (parts 306D to 306F).

[0098] Figure 3J The next stage of cooling the heat-generating device 308 using the cooling system 300 is depicted. Specifically, the electromagnet 304D has been deactivated, while the electromagnet 304G has been activated. This has divided the magnetothermal medium 302 into an inactive region 322A and an activated region 322B. Notably, as shown, the activated region 322B is directly connected to the system radiator 310. Therefore, although a portion of 306G currently has excess heat capacity, the heat within the activated region 322B can now dissipate to the system radiator 310. In fact, Figures 3L to 3P The disabling of electromagnets 304E to 304G will be shown, thereby effectively pumping heat to the system radiator 310.

[0099] Figure 3KThe initial results of this stage are depicted. Excess heat from section 306D has diffused to region 322B, and heat has reached equilibrium throughout region 322B. Notably, heat may begin to diffuse from region 322B to system radiator 310 at this point. However, this heat diffusion may be slow because sections 306E to 306G have no excess heat energy due to the activation of electromagnets 304E–304G. Therefore, in some cases, all electromagnets 304E–304G can be deactivated at this time, thereby reducing the heat capacity of sections 306E–306G. This will generate excess heat energy within sections 306E–306G, promoting heat diffusion from region 322B to system radiator 310.

[0100] However, simultaneously disabling electromagnets 304E–304G also reduces the thermal conductivity of the magnetocaloric material within parts of 306E–306G. This may slow the diffusion of heat, for example, from the left side of section 306E to the right side of section 306G and to the system heat sink 310. Therefore, excess heat may more easily diffuse from section 306E to section 306D. For this reason, in some cases, it may be more advantageous to sequentially continue disabling electromagnets 304E–304G, thereby effectively pumping heat into the system heat sink 310.

[0101] therefore, Figure 3L The next stage of cooling the heat-generating device 308 using the cooling system 300 is described. Specifically, the electromagnet 304E has been deactivated, resulting in portion 306E containing excess heat. Because portions 306F and 306G are located in the active region 324C, while portion 306D is located in the inactive region 324B, portions 306F and 306G have significantly higher thermal conductivity than portion 306D. As a result, the excess heat in portion 306E will tend to diffuse into portions 306F and 306G. This may result in portions 306F and 306G containing excess heat, but this heat can subsequently diffuse to the system radiator 310.

[0102] It is worth noting that, Figure 3K and Figure 3L The display shows that the heat-generating equipment 308 continuously increases its thermal energy. Figure 3L It also shows that electromagnet 304A is activated, thereby increasing the heat capacity and thermal conductivity of part of 306A. This results in a second activated area, namely activated area 324A. Note that in some use cases, electromagnet 304A can be automatically activated after electromagnet 304E is deactivated, thus automatically restarting. Figure 3B This is the first time that an electromagnet activation mode has been shown in this paper. In certain application scenarios, electromagnet 304A can be activated when the temperature of the heat-generating device 308 is detected to have exceeded the upper temperature threshold.

[0103] In addition, in some cases, such as Figure 3B As shown, in Figure 3L It might be beneficial to activate all electromagnets 304A-304C together. Alternatively, in Figure 3L They can activate electromagnets 304A-304B together. However, in Figure 3L Only the electromagnet 304A is shown being activated, in order to more fully depict the fluctuating characteristics of the heat pump operation of the cooling system 300.

[0104] therefore, Figure 3M The next stage, utilizing the cooling system 300 to cool the heat-generating device 308, is depicted. Figure 3M In this process, electromagnet 304F has been deactivated, resulting in portion 306F containing excess heat. This excess heat will diffuse to portion 306G, which has significantly higher thermal conductivity and heat capacity. This can accelerate the diffusion of heat previously in portion 306G to the system heat sink 310.

[0105] In addition, Figure 3M The electromagnet 304B has been reactivated. Therefore, heat can continue to diffuse from the heat-generating device 308 into the magnetocaloric medium 302 (specifically, into portions 306A and 306B of region 326A). As shown in the figure, in Figure 3M The magnetothermal medium 302 has been divided into three regions: regions 326A, 326B and 326C.

[0106] Figure 3N The next stage, utilizing the cooling system 300 to cool the heat-generating device 308, is depicted. Figure 3N In this configuration, electromagnet 304G has been deactivated, resulting in a portion of 306G containing excess heat. However, since portion 306F is also in an inactive region (region 328B), it has low thermal conductivity. For this reason, most of the excess heat within portion 306G will dissipate to the system heat sink 310.

[0107] Furthermore, the electromagnet 304C has been reactivated, increasing the heat capacity of 306C. As a result, the heat capacity of the region most closely connected to the heat-generating device 308 increases, promoting further heat diffusion from the heat-generating device 308 to the magnetocaloric medium 302. Therefore, the heat-generating device 308 is further cooled.

[0108] Figure 3O Describing the process Figure 3N The cooling system 300 discusses the heat diffusion process. Specifically, excess heat from portion 306G has been transferred to the system radiator 310, and the heat is further transferred from the heat-generating device 308 to portions 306A-306C, where the heat has reached equilibrium. In other words, Figure 3O The cooling system 300 in the middle is shown as... Figure 3CThe state shown is similar. From this point onward, the heat pump operation of the cooling system 300 can proceed as initially... Figure 3D-3N Continue as shown.

[0109] To further illustrate the potential circulation characteristics of the cooling system 300, Figure 3P It depicts the next stage of operation for the cooling system 300, similar to... Figure 3D The initial stage is shown. In some application scenarios, during the operation of the heat-generating equipment 308, the cooling system 300 can continuously circulate through... Figures 3B to 3N The various stages are shown.

[0110] It is worth noting that, Figures 3A to 3P Most of the figures in the disclosure depict the activation of three electromagnets at each stage. This may be ideal in some use cases, but it is done in this disclosure to effectively illustrate the heat pump characteristics of the cooling system 300 in operation. Therefore, the embodiments of this disclosure should not be construed as applicable only to heat pump cooling systems that simultaneously activate three groups of electromagnets.

[0111] Similarly, Figure 3A-3P The electromagnet in the deactivated tailing activity section is shown (e.g., Figure 3O (Part 306A) while simultaneously activating the electromagnet corresponding to the inactive part of the head (e.g., Figure 3O (See section 306D). While this is also done in this disclosure to effectively illustrate the heat pump characteristics of the cooling system 300 in operation, simultaneous activation and deactivation may be beneficial in some applications. However, in other applications, activating and deactivating these electromagnets separately may be more advantageous.

[0112] For example, in some use cases, an electromagnet adjacent to a leading inactive part can be activated before deactivating an electromagnet adjacent to a trailing active part. For example, in Figure 3O This is similar to activating electromagnet 304D before deactivating electromagnet 304A. In some applications, this can cause heat to diffuse from portions 306A-306C to portion 306D before portion 306A is isolated from the magnetic field. Furthermore, this prevents heat from diffusing back from portion 306A to the heat-generating device 308 when electromagnet 304A is subsequently deactivated. However, since the heat in portion 306A has not yet been pumped out of portion 306A, this may also cause heat to diffuse from portion 306E to portion 306D. Therefore, when the inactive portion of the current conductor is directly connected to the system heat sink (e.g., as...), Figure 3I As shown in the figure, this strategy may be the most useful.

[0113] Similarly, in certain use cases, an electromagnet adjacent to a following active part can be deactivated before activating the electromagnet adjacent to the preceding inactive part. For example, in Figure 3O This is similar to deactivating electromagnet 304A before activating electromagnet 304D. In some applications, this can cause heat to diffuse into the various portions of the activated region (e.g., portions 306B and 306C) before activating the leading inactive portion (e.g., portion 306D). Once the leading inactive portion is exposed to the magnetic field, this prevents heat from diffusing back into the leading inactive portion from downstream portions (e.g., preventing heat from diffusing back into 306D from portion 306E when electromagnet 304D is activated).

[0114] However, this could also cause heat to diffuse from the trailing active portion to the upstream portion or the heat-generating device, while the leading inactive portion has not yet been exposed to the magnetic field (e.g., causing heat to diffuse from portion 306A to the heat-generating device 308 before portion 304D is exposed to the magnetic field). Therefore, this strategy may be least suitable when the trailing active portion is connected to the heat-generating device close to other portions (e.g., directly connected to the heat-generating device, or connected to a thermally resistant material directly connected to the heat-generating device).

[0115] The leader electromagnet can be activated before the trailing electromagnet is deactivated. This will cause heat to diffuse into the leader section earlier, preventing heat from the trailing section from diffusing back from the downstream section. However, this may cause heat to diffuse from the next section into the leader section. The trailing edge can also be deactivated before the leader edge is activated. This may cause heat to diffuse into the leader region before the leader edge is activated. This prevents heat from diffusing back into the leader section. However, this may cause heat to diffuse from the trailing section into the upstream section.

[0116] For ease of understanding, Figure 4 An exemplary process using a cooling system, including a set of electromagnets, is illustrated, which can be used to pump heat through a magnetothermal medium, similar to cooling system 300. Method 400 begins at block 402, where the device temperature of the heat-generating equipment is detected to be above a threshold temperature. For example, this could take the form of detecting the temperature of heat-generating equipment 308.

[0117] It is worth noting that in some methods of operating a cooling system similar to cooling system 300, box 402 may be considered an optional step. For example, if the cooling system operates continuously in heat pump circulation during the operation of the heat-generating equipment, box 402 may be unnecessary.

[0118] Method 400 continues in block 404, wherein a first region of the magnetocaloric medium is exposed to a magnetic field (or a set of magnetic fields). This can, for example, take the form of activating a set of electromagnets adjacent to the region, such as... Figure 3BThe region 314A is adjacent to electromagnets 304A-304C. In some embodiments, the group of electromagnets may include a single electromagnet, while in other embodiments, the group may include more than one electromagnet.

[0119] Method 400 continues in block 406, wherein a target temperature is detected in the heat-generating device. In some embodiments, this may be similar to detecting... Figure 3C The heat-generating device 308 in the magnetocaloric medium has reached a threshold low temperature. In some embodiments, block 406 may help ensure that the heat-generating device has cooled to the desired temperature before the portion of the magnetocaloric medium closest to the heat-generating device is isolated from the magnetic field. However, in some embodiments, the electromagnet adjacent to the magnetocaloric medium may be activated and deactivated as part of a periodic pattern or timer. For example, this could be taken in a self- Figure 3B After a predetermined time period following the activation of the electromagnet 304A, Figure 3D The electromagnet 304A is used in the middle.

[0120] Method 400 continues in block 408, wherein the cooling system switches the magnetic field (or a set of magnetic fields) to the next region of the magnetocaloric medium. In some embodiments, this may take the form of deactivating one or more electromagnets adjacent to a portion of the magnetocaloric medium in the first region and activating one or more electromagnets adjacent to a portion of the magnetocaloric medium in the next region. In some embodiments, as Figure 3C and 3D As shown in regions 314A and 316B, the next region may overlap with the first region. In other embodiments, the two regions may not overlap, for example... Figure 3C and 3H Areas 314A and 320B.

[0121] Method 400 continues in block 410, wherein it is determined whether the latest region of the magnetocaloric medium to which the magnetic field was switched in block 408 is the final region in the magnetocaloric medium. In some embodiments, this may include confirming that the region is directly connected to the system heat sink. In other embodiments, this may include confirming that the region corresponds to the last electromagnet preceding the system heat sink (e.g., Figure 3M (Magnet 340G).

[0122] If it is determined in box 410 that the region is not the final region (e.g., Figure 3HIf region 320B is identified, then method 400 returns to box 408 to iterate through boxes 408 and 410. Alternatively, if it is determined in box 410 that the region is the final region, method 400 proceeds to box 412, where the cooling system allows heat from the final region to be transferred to the system radiator. In some embodiments, this may take the form of waiting for a predetermined amount of time. In some embodiments, this may take the form of waiting until the magnetocaloric medium cools to a threshold low temperature in the final region.

[0123] Once heat transfer to the system radiator is allowed in box 412, method 400 proceeds to box 414, in which the final area is isolated from the magnetic field.

[0124] In some embodiments, method 400 may repeat the execution of blocks 402-414 after execution block 414. In some embodiments, method 400 may continue execution of block 404 after execution block 414. In other embodiments, method 400 may terminate after block 414.

[0125] Some embodiments of this disclosure may involve isolating relatively large heat transfer media from a magnetic field so that these media are in a state capable of transferring the heat energy stored therein to the surrounding environment. However, as previously mentioned, isolating a magnetothermal heat transfer medium from a magnetic field not only reduces its heat capacity but also its thermal conductivity. In some particularly large media, this can result in heat being dissipated from the medium very slowly.

[0126] For example, in some embodiments of this disclosure, a magnetocaloric radiator (such as magnetocaloric radiator 102) or a portion of the magnetocaloric medium (such as portion 306A) is isolated from the magnetic field. However, if the magnetocaloric radiator 102 or portion 306A has a relatively large size, the heat located on the far left of the radiator / portion (e.g., Figure 1H The heat from the upper left corner of the magnetic radiator 102 (in the middle) reaches the next heat transfer medium (e.g., Figure 1H Before the magnetothermal switch 106, it may need to travel a long distance through the rest of the heat sink / part of the main body. Due to the low thermal conductivity of the dielectric material, the heat energy may take a long time to leave the dielectric.

[0127] In such embodiments, it may be advantageous to design a heat transfer medium with heat transfer supplements to increase the rate at which heat energy can leave the medium.

[0128] Figure 5 Such an embodiment is shown. Figure 5A heat transfer medium 502 is shown. The heat transfer medium 502 is shown as a magnetothermal radiator, but it can also take the form of a portion of a magnetothermal medium. The heat transfer medium 502 is connected to a magnetothermal switch 504 on the left and to a magnetothermal switch 506 on the right. It is noteworthy that in embodiments where the heat transfer medium 502 takes the form of a portion of a magnetothermal medium, the magnetothermal switch 506 can take the form of another portion of the magnetothermal medium or a system radiator. Similarly, the magnetothermal switch 504 can take the form of another portion of the magnetothermal medium, a heat-generating device, or a thermal resistance component.

[0129] The heat transfer medium 502 also shows a heat transfer supplement 508 applied thereon. The heat transfer supplement 508 may be in the form of a material with high thermal conductivity, which is applied to the surface of the heat transfer medium 502. For example, the heat transfer supplement 508 may be in the form of copper wire wound on the heat transfer medium 502, or in the form of a copper layer formed on the heat transfer medium 502.

[0130] The heat transfer supplement 508 can be used to provide a low-resistance path for heat to diffuse from one side of the heat transfer medium 502 to the other. For example, if the heat transfer medium 502 is isolated from the magnetic field, the heat capacity of the heat transfer medium 502 will decrease, resulting in excess heat energy within the heat transfer medium 502. However, the presence of the heat transfer supplement provides an efficient path for some of the heat energy to diffuse to the magnetothermal switch 506. Specifically, for example, excess heat energy on the left side of the heat transfer medium 502 does not need to pass through the low-conductivity material of other parts of the heat transfer medium 502, but can diffuse to the heat transfer supplement 508, and from there spread relatively quickly throughout the heat transfer supplement 508 and reach the magnetothermal switch 506.

[0131] As previously described, embodiments of this disclosure relate to the independent activation of one or more sets of electromagnets to enable a magnetocaloric medium to act as a heat pump. To aid in understanding these embodiments, Figure 6A-6R The various stages in forming this cooling system are shown.

[0132] Figure 6A and 6B Two views are shown illustrating the first stage of forming the cooling system 600. Specifically, Figure 6A A top view (i.e., a plan view) of the cooling system 600 is depicted, and Figure 6B A side view (i.e., a cross-sectional view) of the cooling system 600 is depicted. In fact, throughout the entire... Figure 6A-6R In the drawing, the figure on the left depicts a top view of the cooling system 600, while the figure on the right depicts a side view of the cooling system 600. In this first stage, a substrate 602 is provided on which the cooling system can be formed.

[0133] Figure 6C and Figure 6DTwo views depict the second stage of forming the cooling system 600. In this second stage, a conductive material layer 604, such as copper or gold, is formed on a substrate 602. For example, layer 604 can be formed using chemical vapor deposition, sputtering, or atomic layer deposition using a precursor.

[0134] Figure 6E and Figure 6F Two views depict the third stage of forming the cooling system 600. In this third stage, layer 604 has been patterned into a series of metal lines 606A–606J (i.e., patterned wires). For example, this patterning can be performed by depositing a photomask on the portion of layer 604 represented by the metal lines 606A–606J and performing directional etching (e.g., reactive ion etching) on ​​the portions of layer 604 not covered by the photomask.

[0135] Figure 6G and 6H Two views depict the fourth stage of forming the cooling system 600. In this fourth stage, a dielectric layer 608 has been formed over the substrate 602 and metal lines 606A–606J. In some embodiments discussed below, the dielectric layer 608 is advantageously a thin layer (e.g., 50 nm) and formed of a material with extremely low thermal conductivity (e.g., SiO2).

[0136] Figure 6I and 6J Two views depict the fifth stage of forming the cooling system 600. In this fifth stage, a dielectric layer 608 is etched over metal lines 606I and 606J, thereby providing pathways to the metal lines 606I and 606J for the device contacts. This can be performed using directional etching.

[0137] Figure 6K and 6L Two views depict the sixth stage of forming the cooling system 600. In this sixth stage, a layer of magnetocaloric material 610 is stacked on the dielectric layer 608 and contact points 606I and 606J. The magnetocaloric material 610 may take the form of, for example, a topological half-metal (such as niobium phosphide).

[0138] Figure 6M and 6N Two views depict the seventh stage of forming the cooling system 600. In this seventh stage, the magnetocaloric material 610 layer has been patterned into a heat transfer medium 612. This can be achieved, for example, by... Figure 6M This is achieved by applying a photoresist layer to a portion of the magnetocaloric material 610 represented by the heat transfer medium 612 and performing directional etching on the remaining portion of the magnetocaloric material 610.

[0139] Figure 6O and 6PTwo views depict the eighth stage of forming the cooling system 600. In this eighth stage, the heat-generating device 614 has been patterned on the heat transfer medium 612. The operation of the cooling system 600 can be understood at this stage. Specifically, the metal wires 606C-606J are in the form of electromagnets that can be activated (e.g., an electric current can flow through them) to generate a magnetic field above them. These electromagnets can be independently controlled to expose corresponding portions of the heat transfer medium 612 to the magnetic field and increase its heat capacity.

[0140] For example, by activating electromagnet 606C, the heat capacity of the heat transfer layer 612 directly below the heat-generating device 614 can be significantly increased, thereby increasing the diffusion of heat energy from the heat-generating device 614 to the heat transfer medium 612. Then, electromagnets 606C-606J can be activated in a wave-like pattern similar to that of the electromagnets in Figure 3, causing the heat energy to be pumped to the right and flow out of the heat transfer medium 612.

[0141] Figure 6Q and 6R An optional ninth stage for forming the cooling system 600 is depicted. In this optional ninth stage, the dielectric layer 608 has been removed. This can advantageously increase the thermal insulation of the heat generated by the heat-generating device 614. In other words, removing the dielectric layer 608 can help prevent the heat energy diffusing from the heat-generating device 614 to the heat transfer medium 612 from further diffusing to the metal wires 606C-606H.

[0142] As previously described, some embodiments of this disclosure relate to a cooling system having a magnetothermal radiator and two magnetothermal switches. To aid in understanding these embodiments, Figure 7A-7L The various stages in forming this cooling system are shown.

[0143] Figure 7A and 7B Two views are shown illustrating the first stage of forming the cooling system 700. Specifically, Figure 7A A top view (i.e., a plan view) of the cooling system 700 is depicted, and Figure 7B A side view (i.e., a cross-sectional view) of the cooling system 700 is depicted. In fact, throughout the entire... Figure 7A-7L In the drawing, the top view of the cooling system 700 is depicted, while the bottom view depicts a side view of the cooling system 700. In this first stage, a substrate 702 is provided on which the cooling system can be formed.

[0144] Figure 7C and 7DTwo views depict the second stage of forming system 700. In this second stage, a conductive material layer 704, such as copper or gold, is formed on substrate 702. For example, layer 704 can be formed using chemical vapor deposition, sputtering, or atomic layer deposition using a precursor.

[0145] Figure 7E and 7F Two views depict the third stage of forming the cooling system 700. In this third stage, layer 704 has been patterned into microcoils 706A–706C (i.e., planar patterned metal lines in coil shape). For example, this patterning can be achieved by depositing a photomask on the portion of layer 704 represented by the microcoils 706A–706C and performing directional etching (e.g., reactive ion etching) on ​​the portions of layer 704 not covered by the photomask.

[0146] Figure 7G and 7H Two views depict the fourth stage of forming the cooling system 700. In this fourth stage, a dielectric layer 708 has been formed over the substrate 702 and the microcoils 706A–706C. In some embodiments discussed below, the dielectric layer 708 is preferably a thin layer (e.g., 50 nm) and formed of a material with extremely low thermal conductivity (e.g., SiO2).

[0147] Figure 7I and 7J Two views depict the fifth stage of forming the cooling system 700. In this fifth stage, magnetothermal switches 710 and 712 and a magnetothermal heat sink 714 are patterned onto the dielectric layer 708. Magnetothermal switches 710 and 712 are formed adjacent to microcoils 706A and 706C, respectively, which exposes them to a magnetic field when current flows through them. Similarly, the magnetothermal heat sink 714 is formed adjacent to microcoil 706B, which exposes it to a magnetic field when current flows through it.

[0148] Those skilled in the art will understand that the specific method for patterning the magnetocaloric switches 710 and 712 and the magnetocaloric heat sink 714 onto the substrate 708 can vary depending on the implementation. For example, in an embodiment where the magnetocaloric switches 710 and 712 and the magnetocaloric heat sink 714 are all made of the same magnetocaloric material (e.g., the same topological half-metal), a thick layer of this magnetocaloric material can be deposited over the entire surface of the dielectric layer 708. Figure 7J As shown, the thick layer can reach the top of the magnetothermal radiator 714.

[0149] Then it can be done by placing it on top of the thick layer. Figure 7IAn etching mask is applied to the top contour-matching portion of the magnetothermal heat sink 714 to pattern the magnetothermal heat sink 714. Timed directional etching, such as chemical mechanical planarization (also referred to herein as "chemical mechanical polishing"), can then be performed on the thick layer to reduce its height to [missing information]. Figure 7J The top of the magnetothermal switches 710 and 712 shown.

[0150] The magnetocaloric switches 710 and 712 can then be patterned by applying another etch mask over a portion of the thinned top layer, which is consistent with... Figure 7I The top contours of the magnetocaloric switches 710 and 712 shown match. A second directional etching can be performed to remove any remaining magnetocaloric material not covered by the photomask. For example, this second directional etching can be chemical mechanical polishing (CMP), which utilizes an etchant with high selectivity for the magnetocaloric material and low selectivity for the dielectric layer 708, thus allowing the dielectric layer 708 to act as an etch stop layer. After these etchings, the remaining magnetocaloric material will take the shape of the magnetocaloric switches 710, 712, and the magnetocaloric heat sink 714. The photomask on top of the magnetocaloric switches 710, 712, and the magnetocaloric heat sink 714 can then be removed.

[0151] However, in some cases, the magnetothermal switches 710 and 712, as well as the magnetothermal heat sink 714, can be patterned individually. For example, in some embodiments, the magnetothermal switches 710 and 712 can be fully formed before or after the magnetothermal heat sink 714 is formed. This may be particularly useful in embodiments where the magnetothermal heat sink 714 is not made of the same material as the magnetothermal switches 710 and 712.

[0152] For example, a thin layer of a first magnetocaloric material (e.g., TaAs) can be formed on the dielectric layer 708. This thick layer can extend to, for example... Figure 7J The top of the magnetothermal switches 710 and 712 are shown. Then, it can be connected to the top of the thinned thick layer... Figure 7I An etching mask is applied to the portions of the top contours of the magnetocaloric switches 710 and 712 to pattern them. This allows for highly selective etching of the first magnetocaloric material relative to the material of the dielectric layer 708. The remaining magnetocaloric material after this etching will then conform to the shape of the magnetocaloric switches 710 and 712.

[0153] A thick layer of a second magnetocaloric material (e.g., NbP) can then be formed on the dielectric layer 708 and the etch mask remaining on top of the magnetocaloric switches 710 and 712. This thick layer may extend to, for example, Figure 7J The top of the magnetothermal radiator 714 shown.

[0154] The magnetic heat sink 714 can then be patterned by applying an etching mask to the portion of the thick layer that matches the top contour of the magnetic heat sink 714, such as... Figure 7I As shown. To improve accuracy, some etch masks can also be applied to the thick layer portions formed above the magnetothermal switches 710 and 712, which protrude compared to the rest of the thick layer. A timed chemical mechanical polishing (CMP) etching can then be performed, which will remove all the higher etch masks on the thick layer above the magnetothermal switches 710 and 712, but will not remove the etch mask corresponding to the top contour of the magnetothermal radiator 714.

[0155] A third CMP can then be performed using an etchant that is highly selective for etching masks on the thick layer of the second magnetocaloric material, as well as on the top of the magnetocaloric switches 710 and 712. After this etching, the remaining second layer of magnetocaloric material will be in the shape of a magnetocaloric radiator 714. The etch masks on the top of the magnetocaloric radiator 714 and the top of the magnetocaloric switches 710 and 712 can then be removed.

[0156] Figure 7I and 7J The fifth stage of forming the cooling system 700 also depicts contact points 716 for heat-generating devices. Contact points 716 can be copper or gold patterned on dielectric layer 708, for example, by applying a thin layer of contact material, applying an etch mask, and CMP similar to the example processes for forming magnetothermal switches 710 and 712 and magnetothermal heat sink 714.

[0157] Figure 7I and Figure 7J The fifth stage of forming the cooling system 700 also depicts contact points 718 of the system heat sink. In some embodiments, these contact points may be in the form of a metal with high thermal conductivity. In some embodiments, these contact points may actually be considered part of the system heat sink.

[0158] The formation process of contact point 718 can be as follows: First, an etching mask is formed on dielectric layer 708, the pattern of which is similar to... Figure 7I The top profile shape of the contact point 718 shown is reversed. Chemical mechanical polishing (CMP) etching can then be performed using an etchant that is highly selective to the dielectric layer 708 material compared to the substrate 702 material. This will allow the substrate 702 to act as an etch stop layer for the CMP. The contact point 718 can then be formed using a masking and etching process similar to that described above for forming the magnetocaloric switches 710 and 712 and the magnetocaloric heat sink 714.

[0159] Figure 7K and 7LTwo views depict the sixth stage of forming the cooling system 700. In this sixth stage, the heat-generating device 720 has been placed on the contact point 716. Furthermore, the dielectric layer 708 has been removed, which advantageously increases the thermal insulation of the heat generated by the heat-generating device 720. In other words, removing the dielectric layer 708 helps prevent the heat energy diffusing from the heat-generating device 720 to the contact point 716 and the magnetocaloric material 710 from further diffusing to the microcoil 706A or the substrate 702.

[0160] At this stage, the operation of the cooling system 700 can be understood. Specifically, by activating the microcoil 706B, the heat capacity of the magnetothermal radiator 714 increases. Further, by activating the microcoil 706A, the thermal conductivity of the magnetothermal switch 710 increases. Therefore, the heat generated by the heat-generating device 720 can be transferred to the magnetothermal radiator 714 through the magnetothermal switch 710. By deactivating the microcoil 706A, the thermal conductivity of the magnetothermal switch 710 can be reduced. This prevents heat that has dissipated from the magnetothermal radiator 714 from returning to the heat-generating device 720 through the magnetothermal switch 710.

[0161] After isolating heat within the magnetothermal radiator 714 by disabling microcoil 706A, activating microcoil 706C exposes magnetothermal switch 712 to a magnetic field, thereby increasing its thermal conductivity. This allows heat to diffuse from magnetothermal radiator 714 to contact point 718, and then heat from contact point 718 can diffuse to the rest of the system's radiator. Furthermore, by disabling microcoil 706B, the heat capacity of magnetothermal radiator 714 can be significantly reduced, causing heat to tend to leave magnetothermal radiator 714. Since magnetothermal switch 710 is in a low thermal conductivity state while magnetothermal switch 712 is in a high thermal conductivity state, heat will enter contact point 718 through magnetothermal switch 712.

[0162] Some embodiments of this disclosure may take the form of a first cooling system. The first cooling system may include a magnetothermal radiator, a device magnetothermal switch, and a radiator magnetothermal switch. The device magnetothermal switch connects the heat-generating device to the magnetothermal radiator, and the radiator magnetothermal switch connects to the system radiator. In these embodiments, the cooling system can be used as a steady-state cooling system capable of utilizing magnetothermal adiabatic cooling without the need for moving parts.

[0163] In some embodiments of the first cooling system, a radiator magnetothermal switch connects the magnetothermal radiator directly to the system radiator. In these embodiments, the radiator magnetothermal switch can be used to enable or disable heat transfer between the magnetothermal radiator and the system radiator.

[0164] In some embodiments of the first cooling system, the magnetothermal radiator, the device magnetothermal switch, and the radiator magnetothermal switch are made of the same material. This improves manufacturing efficiency.

[0165] In some embodiments of the first cooling system, the magnetothermal radiator is made of a different material than the device magnetothermal switch and the radiator magnetothermal switch. This cooling system allows for the selection of materials for the magnetothermal radiator and magnetothermal switch that are particularly effective for the function of these components.

[0166] In some embodiments of the first cooling system, the heat sink is formed of a semi-metal. In some such embodiments, the semi-metal may be niobium phosphide. In these embodiments, the significant magnetocaloric properties of niobium phosphide can improve the effectiveness of the first cooling system.

[0167] In some embodiments of the first cooling system, the cooling system includes an electromagnet located adjacent to the magnetocaloric heat sink. This allows for control of the heat capacity and thermal conductivity of the magnetocaloric heat sink. In some of these embodiments, the electromagnet may be in the form of a solenoid. Such a solenoid is capable of generating a strong magnetic field. In some embodiments, the electromagnet may be in the form of a flat, patterned coil. Such a coil can be scaled down for use in very small cooling systems.

[0168] In some embodiments of the first cooling system, the cooling system includes a first electromagnet located at a magnetothermal switch adjacent to the device, a second electromagnet located adjacent to a magnetothermal radiator, and a third electromagnet located adjacent to a magnetothermal switch of the radiator. Such embodiments allow for independent control of the first, second, and third electromagnets.

[0169] Some embodiments of this disclosure can take the form of a second cooling system. This second cooling system includes a magnetocaloric medium, a first set of electromagnets, and a second set of electromagnets. The magnetocaloric medium is connected to a heat-generating device and a system radiator. The first set of electromagnets is located in a first region adjacent to the magnetocaloric medium. The first region is adjacent to the heat-generating device. The second set of electromagnets is located in a second region adjacent to the magnetocaloric medium. The second region is adjacent to the system radiator. The second cooling system allows for independent control of the first and second sets of electromagnets, enabling the magnetocaloric medium to function as a heat pump.

[0170] In some embodiments of the second cooling system, the second cooling system includes a third set of electromagnets located adjacent to a third region of the magnetocaloric medium. The third region partially overlaps with the first region. This allows for precise heat transfer between the first and third regions.

[0171] In some embodiments of the second cooling system, the first set of electromagnets includes a first electromagnet and a second electromagnet, and the third set of electromagnets includes a second electromagnet and a third electromagnet. This can further enable precise heat transfer between the first and third regions.

[0172] In some embodiments of the second cooling system, the first set of electromagnets includes a first electromagnet and a second electromagnet. The first electromagnet is located adjacent to a first portion of the magnetocaloric medium. The second electromagnet is located adjacent to a second portion of the magnetocaloric medium.

[0173] In some embodiments of the second cooling system, the electromagnets in the first set of electromagnets are in the form of a set of patterned wires. This allows for efficient manufacturing of the first set of electromagnets.

[0174] In some embodiments of the second cooling system, the second cooling system includes a thermal insulation layer located between the magnetocaloric medium and the heat-generating device. This prevents heat energy from being transferred from the magnetocaloric medium to the heat-generating device.

[0175] Some embodiments of this disclosure can take the form of a third cooling system. The third cooling system includes a system heat sink and a first magnetocaloric heat transfer medium. The first magnetocaloric heat transfer medium is connected to the system heat sink. The first magnetocaloric heat transfer medium includes a semi-metal. This can achieve a significant magnetocaloric effect in the first magnetocaloric heat transfer medium, thereby improving the effectiveness of the third cooling system in solid-state designs.

[0176] In some embodiments of the third cooling system, the first magnetothermal heat transfer medium takes the form of an intermediate magnetothermal radiator.

[0177] In some embodiments of the third cooling system, the third cooling system further includes a first set of electromagnets adjacent to a first region of the first magnetocaloric heat transfer medium, and a second set of electromagnets adjacent to a second region of the first magnetocaloric heat transfer medium. This allows the first magnetocaloric heat transfer medium to act as a heat pump.

[0178] In some embodiments of the third cooling system, the semimetal is niobium phosphide. This further enables a significant magnetocaloric effect in the first magnetocaloric heat transfer medium, thereby improving the effectiveness of the third cooling system in solid-state designs.

[0179] In some embodiments of the third cooling system, the third cooling system further includes a second magnetocaloric medium. The second magnetocaloric medium comprises tantalum arsenide. This allows for the selection of materials for the first and second magnetocaloric media that are particularly effective for the function of those components.

[0180] Some embodiments of this disclosure can take the form of a method for cooling a heat-generating device. This method may include activating a first set of electromagnets adjacent to the magnetocaloric medium. Activating the first set of electromagnets divides the magnetocaloric medium into activated and inactive regions. This can at least partially enable the magnetocaloric medium to function as a heat pump.

[0181] In some embodiments of the method, the method further includes deactivating the first set of electromagnets. The method also includes activating the second set of electromagnets. Activating the second set of electromagnets results in a second activated region in the magnetocaloric medium. This can further enable the magnetocaloric medium to act as a heat pump.

[0182] In some embodiments of this method, the activated region has a higher specific heat capacity than the inactive region. This can further enable the magnetocaloric medium to act as a heat pump.

[0183] The description of various embodiments of the present invention is presented for illustrative purposes and is not intended to be exhaustive or to limit the scope to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein has been chosen to best explain the principles of the embodiments, practical applications of existing technology in the market, or technical improvements thereof, or to enable those skilled in the art to understand the embodiments disclosed herein.

Claims

1. A cooling system, comprising: Magnetic thermal radiator; A magnetic thermal switch for connecting a heat-generating device to the magnetic thermal radiator; A radiator magnetoresistive switch, which is connected to the system radiator.

2. The cooling system according to claim 1, wherein the radiator magnetothermal switch directly connects the magnetothermal radiator to the system radiator.

3. The cooling system according to claim 1, wherein the magnetothermal radiator, the device magnetothermal switch, and the radiator magnetothermal switch are made of the same material.

4. The cooling system according to claim 1, wherein the magnetothermal radiator is made of a different material than the magnetothermal switch of the device and the magnetothermal switch of the radiator.

5. The cooling system according to claim 1, wherein the radiator is semi-metallic.

6. The cooling system according to claim 5, wherein the semi-metal is niobium phosphide.

7. The cooling system of claim 1 further includes an electromagnet located adjacent to the magnetothermal radiator.

8. The cooling system according to claim 7, wherein the electromagnet is in the form of a solenoid.

9. The cooling system according to claim 7, wherein the electromagnet is in the form of a flat patterned coil.

10. The cooling system according to claim 1, further comprising: The first electromagnet is located near the magnetothermal switch of the device; The second electromagnet is located adjacent to the magnetothermal radiator; as well as The third electromagnet is located near the magnetothermal switch of the radiator.

11. A cooling system, comprising: Magnetothermic medium, which is connected to heat-generating equipment and system radiators; The first group of electromagnets is located in a first region adjacent to the magnetocaloric medium, wherein the first region is adjacent to the heat-generating device. as well as The second set of electromagnets is located in a second region adjacent to the magnetothermal medium, wherein the second region is adjacent to the system heat sink.

12. The cooling system of claim 11 further includes a third set of electromagnets located in a third region adjacent to the magnetocaloric medium, wherein the third region partially overlaps with the first region.

13. The cooling system of claim 12, wherein the first group of electromagnets comprises a first electromagnet and a second electromagnet, and wherein the third group of electromagnets comprises the second electromagnet and the third electromagnet.

14. The cooling system of claim 11, wherein the first set of electromagnets comprises a first electromagnet and a second electromagnet, wherein the first electromagnet is located adjacent to a first portion of the magnetocaloric medium, and wherein the second electromagnet is located adjacent to a second portion of the magnetocaloric medium.

15. The cooling system of claim 11, wherein the electromagnets in the first set of electromagnets are in the form of a set of patterned wires.

16. The cooling system of claim 11 further includes a heat insulation layer located between the magnetothermal medium and the heat-generating device.

17. A cooling system, comprising: System heat sink; A first magnetocaloric heat transfer medium connected to the system heat sink, wherein the first magnetocaloric heat transfer medium comprises a semi-metal.

18. The cooling system according to claim 17, wherein the first magnetocaloric heat transfer medium is in the form of an intermediate magnetocaloric radiator.

19. The cooling system according to claim 17, further comprising: A first group of electromagnets adjacent to a first region of the first magnetocaloric heat transfer medium; as well as A second set of electromagnets adjacent to the second region of the first magnetocaloric heat transfer medium.

20. The cooling system of claim 17, wherein the semi-metal is niobium phosphide.

21. The cooling system of claim 20 further includes a second magnetocaloric heat transfer medium, wherein the second magnetocaloric heat transfer medium comprises tantalum arsenide.

22. A method for cooling a heat-generating device, the method comprising: Activate a first group of electromagnets adjacent to the magnetocaloric medium, wherein activating the first group of electromagnets divides the magnetocaloric medium into an activated region and an inactive region.

23. The method of claim 22, further comprising: Deactivate the first group of electromagnets; as well as Activate the second group of electromagnets, wherein activating the second group of electromagnets generates a second activation region in the magnetocaloric medium.

24. The method of claim 22, wherein the activated region has a higher specific heat capacity than the inactive region.

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