Reversible logic device and control method thereof

Abstract

The embodiment of the invention provides a reversible logic device and a control method thereof, and relates to the technical field of field programmable logic devices.The reversible logic device comprises a composite structure layer and a heavy metal layer, and the composite structure layer comprises a first ferromagnetic layer, a non-magnetic layer and a second ferromagnetic layer which are sequentially stacked; the heavy metal layer is arranged on the side, close to the first ferromagnetic layer, of the composite structure layer, the projection of the composite structure layer to the heavy metal layer coincides with the heavy metal layer, the reversible logic device is of an X-shaped structure, and the input end and the output end of the reversible logic device are located in a first area and a second area respectively. The first region and the second region are respectively positioned at two opposite ends of the X-shaped structure; the magnetization direction of the first ferromagnetic layer and the magnetization direction of the second ferromagnetic layer are opposite and are both perpendicular to the non-magnetic layer, and a synthetic antiferromagnetic coupling skyrmion is generated in the composite structure layer. The performance of the logic device is improved, reversible operation can be realized, the complexity of device design is reduced, and the energy consumption of the device is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of field programmable logic devices, and in particular, to a reversible logic device and a control method thereof. Background Art

[0002] With the development of field programmable gate arrays (FPGAs), the defects of traditional logic devices based on transistors have gradually emerged. The reduction of transistor size leads to an increase in leakage current and power consumption, and the performance of transistor circuits tends to reach its limit. In the face of the requirements of modern electronic devices for high performance, small size, and low power consumption of logic devices, it is urgent to develop a logic device to overcome these limitations.

[0003] Although there are improvements in the prior art for this problem. For example, using logic manipulation based on ferromagnetic skyrmions can, to a certain extent, meet the requirements of electronic devices for high performance, small size, and low power consumption of logic devices. However, in logic devices based on magnetic skyrmions, skyrmions are prone to deviate or move out of the designed track, resulting in poor stability; and skyrmions need to be regenerated every time an operation is performed. After the logic operation is completed, since skyrmions remain in the device, it is easy to affect the secondary operation. Therefore, a large current must be used to annihilate skyrmions. The repeated generation and annihilation of skyrmions not only increase the logic operation link but also increase the energy consumption. Summary of the Invention

[0004] Embodiments of the present invention provide a reversible logic device and a control method thereof to solve the problems of poor stability and high energy consumption of logic devices in the prior art.

[0005] Embodiments of the present invention provide a reversible logic device, including a composite structure layer and a heavy metal layer. The composite structure layer includes a first ferromagnetic layer, a non-magnetic layer, and a second ferromagnetic layer that are sequentially stacked. The heavy metal layer is disposed on one side of the composite structure layer close to the first ferromagnetic layer. The projection of the composite structure layer on the heavy metal layer coincides with the heavy metal layer. Along the projection direction, the reversible logic device has an X-shaped structure. The input end and the output end of the reversible logic device are respectively located in a first region and a second region. The first region and the second region are respectively located at opposite ends of the X-shaped structure;

[0006] The magnetization direction of the first ferromagnetic layer is opposite to that of the second ferromagnetic layer, and both are perpendicular to the non-magnetic layer. Synthetic antiferromagnetic coupled skyrmions are generated in the composite structure layer. The synthetic antiferromagnetic coupled skyrmions are generated by injecting spin-polarized current into the composite structure layer;

[0007] Wherein, when a driving current in a first direction is injected into the heavy metal layer, the synthetic antiferromagnetic coupled skyrmion moves from the first region towards the second region; when a driving current in a second direction is injected into the heavy metal layer, the synthetic antiferromagnetic coupled skyrmion moves from the second region towards the first region. The first direction is opposite to the second direction. The first region is the generation region of the synthetic antiferromagnetic coupled skyrmion, and the second region is the detection region for performing logic gate operation control.

[0008] Optionally, the X-shaped structure includes a first input branch and a second input branch located in the first region, a first output branch and a second output branch located in the second region, and a cross branch located between the first region and the second region. The cross branch is respectively connected to the first input branch, the second input branch, the first output branch, and the second output branch;

[0009] One end of the first input branch away from the cross branch is provided with a first input terminal, and one end of the second input branch away from the cross branch is provided with a second input terminal. The first input terminal and the second input terminal are used to receive input signals of binary data;

[0010] One end of the first input branch close to the cross branch is provided with a first control terminal, and one end of the second input branch close to the cross branch is provided with a second control terminal. The first control terminal is used to control the conduction state between the first input branch and the cross branch according to the input signal corresponding to the first input terminal, and the second control terminal is used to control the conduction state between the second input branch and the cross branch according to the input signal corresponding to the second input terminal;

[0011] One end of the first output branch away from the cross branch is provided with a first output terminal, and one end of the second output branch away from the cross branch is provided with a second output terminal. The first output terminal and the second output terminal are used to detect the arrival state of the synthetic antiferromagnetic coupled skyrmion for performing logic gate operation control.

[0012] Optionally, the first output terminal is the output terminal of an AND gate, and the second output terminal is the output terminal of an OR gate.

[0013] Optionally, the first input branch, the second input branch, the first output branch, and the second output branch are arranged in parallel, and the first input branch and the first output branch are on the same straight line, and the second input branch and the second output branch are on the same straight line;

[0014] Among them, on the cross branch, the first connection line is perpendicular to the second connection line. The first connection line is the connection line of the first input branch and the second output branch on the cross branch, and the second connection line is the connection line of the second input branch and the first output branch on the cross branch.

[0015] An embodiment of the present invention also provides a control method for a reversible logic device, which is applied to the above-mentioned reversible logic device. The method includes:

[0016] When the synthetic antiferromagnetic coupled skyrmion is generated in the composite structure layer of the reversible logic device, a driving current in a first direction is injected into the heavy metal layer;

[0017] The driving current in the first direction injects a spin current into the first ferromagnetic layer through the spin Hall effect in the heavy metal layer, generates a spin transfer torque on the magnetic moment, and the synthetic antiferromagnetic coupled skyrmion moves from the first region to the second region;

[0018] According to the arrival state of the synthetic antiferromagnetic coupled skyrmion in the second region, logic gate operation control is performed;

[0019] After the logic gate operation control is completed, a driving current in a second direction is injected into the heavy metal layer, so that the synthetic antiferromagnetic coupled skyrmion that has moved to the second region moves towards the first region.

[0020] Optionally, before injecting the driving current in the first direction into the heavy metal layer, the method further includes:

[0021] Injecting a spin-polarized current into the composite structure layer to generate the synthetic antiferromagnetic coupled skyrmion, where the synthetic antiferromagnetic coupled skyrmion is obtained by antiferromagnetic coupling according to a first skyrmion and a second skyrmion. The first skyrmion is the corresponding skyrmion in the first ferromagnetic layer, and the second skyrmion is the corresponding skyrmion in the second ferromagnetic layer.

[0022] Optionally, the movement of the synthetic antiferromagnetic coupled skyrmion from the first region to the second region includes:

[0023] Inputting binary data "1" to the first input end and binary data "1" to the second input end;

[0024] The first control end controls the conduction state of the first input branch and the cross branch to be open according to the binary data "1" received by the first input end, so that the synthetic antiferromagnetic coupled skyrmion in the first input branch moves to the cross branch;

[0025] The second control terminal controls the conduction state of the second input branch and the cross branch to be on according to the binary data "1" received by the second input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the second input branch moves to the cross branch;

[0026] The synthetic antiferromagnetic coupled skyrmion in the first input branch and the synthetic antiferromagnetic coupled skyrmion in the second input branch repel each other in the cross branch, so that the synthetic antiferromagnetic coupled skyrmion in the first input branch moves to the first output end of the first output branch, and the synthetic antiferromagnetic coupled skyrmion in the second input branch moves to the second output end of the second output branch.

[0027] Optionally, the movement of the synthetic antiferromagnetic coupled skyrmion from the first region to the second region includes:

[0028] Input binary data "1" to the first input terminal and binary data "0" to the second input terminal;

[0029] The first control terminal controls the conduction state of the first input branch and the cross branch to be on according to the binary data "1" received by the first input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the first input branch moves to the cross branch;

[0030] The second control terminal controls the conduction state of the second input branch and the cross branch to be off according to the binary data "0" received by the second input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the second input branch cannot move to the cross branch;

[0031] Due to the influence of the chiral property, the synthetic antiferromagnetic coupled skyrmion in the first input branch moves to the second output end of the second output branch through the cross branch.

[0032] Optionally, the movement of the synthetic antiferromagnetic coupled skyrmion from the first region to the second region includes:

[0033] Input binary data "0" to the first input terminal and binary data "1" to the second input terminal;

[0034] The first control terminal controls the conduction state of the first input branch and the cross branch to be off according to the binary data "0" received by the first input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the first input branch cannot move to the cross branch;

[0035] The second control terminal controls the conduction state of the second input branch and the cross branch to be on according to the binary data "1" received by the second input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the second input branch moves to the cross branch;

[0036] Due to the influence of the chiral property, the synthetic antiferromagnetic coupled skyrmion in the second input branch moves through the cross branch to the second output terminal of the second output branch.

[0037] Optionally, the movement of the synthetic antiferromagnetic coupled skyrmion from the first region to the second region includes:

[0038] Input binary data "0" to the first input terminal and binary data "0" to the second input terminal;

[0039] The first control terminal controls the conduction state of the first input branch and the cross branch to be off according to the binary data "0" received by the first input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the first input branch cannot move to the cross branch;

[0040] The second control terminal controls the conduction state of the second input branch and the cross branch to be off according to the binary data "0" received by the second input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the second input branch cannot move to the cross branch.

[0041] In the embodiment of the present invention, first, a logic device based on synthetic antiferromagnetic coupled skyrmions is used for logic manipulation. Compared with the logic device based on transistors, the performance of the logic device is greatly improved. Secondly, through the stacked structure of the first ferromagnetic layer, non-magnetic layer and second ferromagnetic layer, synthetic antiferromagnetic coupled skyrmions are formed, eliminating the skyrmion Hall effect during the movement, thereby avoiding the situation where skyrmions touch the edge of the track and annihilate, enhancing the stability and reliability. In addition, the synthetic antiferromagnetic coupled skyrmion is driven by a driving current in the first direction to move towards the second region to achieve logic gate operation control; and after the logic gate operation is completed, the synthetic antiferromagnetic coupled skyrmion is driven by a driving current in the second direction to return from the second region to the first region to achieve a reversible operation, reducing the complexity of device design and the energy consumption of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the embodiments or the description of the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0043] Figure 1 is one of the schematic structural diagrams of the reversible logic device provided by an embodiment of the present invention;

[0044] Figure 2 is the second of the schematic structural diagrams of the reversible logic device provided by an embodiment of the present invention;

[0045] Figure 3 is one of the schematic diagrams of skyrmion movement in the reversible logic device provided by an embodiment of the present invention;

[0046] Figure 4 is the second of the schematic diagrams of skyrmion movement in the reversible logic device provided by an embodiment of the present invention;

[0047] Figure 5 is the flowchart of a control method for a reversible logic device provided by an embodiment of the present invention;

[0048] Figure 6 is the third of the schematic diagrams of skyrmion movement in the reversible logic device provided by an embodiment of the present invention;

[0049] Figure 7 is the fourth of the schematic diagrams of skyrmion movement in the reversible logic device provided by an embodiment of the present invention;

[0050] Figure 8 is the fifth of the schematic diagrams of skyrmion movement in the reversible logic device provided by an embodiment of the present invention;

[0051] Figure 9 is the sixth of the schematic diagrams of skyrmion movement in the reversible logic device provided by an embodiment of the present invention. Detailed implementation manners

[0052] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0053] The terms "first", "second", etc. in the specification and claims of the present invention are used to distinguish similar objects, rather than to describe a specific order or sequence. It should be understood that such structures can be interchanged under appropriate circumstances so that the embodiments of the present invention can be implemented in an order different from those illustrated or described herein, and the objects distinguished by "first", "second", etc. are usually of the same category, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims means at least one of the connected objects, and the character " / ", generally represents an "or" relationship between the associated objects before and after.

[0054] An embodiment of the present invention provides a reversible logic device, which includes a composite structure layer and a heavy metal layer. The composite structure layer includes a first ferromagnetic layer, a non-magnetic layer, and a second ferromagnetic layer that are sequentially stacked. The heavy metal layer is disposed on one side of the composite structure layer close to the first ferromagnetic layer. The projection of the composite structure layer onto the heavy metal layer coincides with the heavy metal layer. Along the projection direction, the reversible logic device has an X-shaped structure. The input end and the output end of the reversible logic device are respectively located in a first region and a second region, and the first region and the second region are respectively located at opposite ends of the X-shaped structure.

[0055] The magnetization direction of the first ferromagnetic layer is opposite to that of the second ferromagnetic layer, and both are perpendicular to the non-magnetic layer. A synthetic antiferromagnetic coupled skyrmion is generated in the composite structure layer, and the synthetic antiferromagnetic coupled skyrmion is generated by injecting a spin-polarized current into the composite structure layer.

[0056] Wherein, when a driving current in a first direction is injected into the heavy metal layer, the synthetic antiferromagnetic coupled skyrmion moves from the first region towards the second region. When a driving current in a second direction is injected into the heavy metal layer, the synthetic antiferromagnetic coupled skyrmion moves from the second region towards the first region. The first direction is opposite to the second direction. The first region is the generation region of the synthetic antiferromagnetic coupled skyrmion, and the second region is the detection region for performing logic gate operation control.

[0057] In an embodiment of the present invention, a reversible logic device is provided. As Figure 1 shown, it mainly includes four layers of structures, namely, a heavy metal layer, a first ferromagnetic layer (FM1), a non-magnetic layer (NM), and a second ferromagnetic layer (FM2) that are sequentially stacked from bottom to top. Among them, the first ferromagnetic layer, the non-magnetic layer, and the second ferromagnetic layer constitute the composite structure layer. As Figure 2 shown, along the projection direction, that is, the top view direction, the reversible logic device has an X-shaped structure. The input end and the output end of the reversible logic device are respectively located in a first region and a second region. The first region and the second region are respectively located at opposite ends of the X-shaped structure. Logic gate operation control can be realized by controlling the movement of the synthetic antiferromagnetic coupled skyrmion between the first region and the second region. Among them, the synthetic antiferromagnetic coupled skyrmion can be generated by injecting a spin-polarized current into the composite structure layer.

[0058] Specifically, the first ferromagnetic layer and the second ferromagnetic layer can be made of the same material, have the same thickness, and a non-magnetic layer is provided therebetween. The magnetization direction of the first ferromagnetic layer is opposite to that of the second ferromagnetic layer, and both are perpendicular to the non-magnetic layer. In this way, by vertically injecting a spin-polarized current into the composite structure layer in the first region, the first skyrmion generated in the first ferromagnetic layer and the second skyrmion generated in the second ferromagnetic layer form a synthetic antiferromagnetic-coupled skyrmion. Moreover, since the magnetic skyrmions (i.e., the first skyrmion and the second skyrmion) in the two ferromagnetic layers (i.e., the first ferromagnetic layer and the second ferromagnetic layer) have opposite polarities, after being coupled together by the interlayer antiferromagnetic coupling effect, the Magnus force directions caused by the opposite polarities of the two ferromagnetic skyrmions are opposite and the magnitudes are equal. There is no skyrmion Hall effect during the movement process, that is, it always moves linearly along the driving direction and will not deviate from the track, reducing the situation where the skyrmion touches the track edge and annihilates, enhancing the stability and reliability.

[0059] When a driving current in the first direction is injected into the heavy metal layer, based on the spin Hall effect, a spin current is generated and vertically injected into the first ferromagnetic layer through the spin-orbit coupling effect, thereby generating a spin torque on the first skyrmion in the first ferromagnetic layer to drive the first skyrmion to move from the first region to the second region; and the corresponding second skyrmion in the second ferromagnetic layer moves synchronously with the first skyrmion under the antiferromagnetic coupling effect, as Figure 3 shown. In other words, when a driving current in the first direction is injected into the heavy metal layer, the synthetic antiferromagnetic-coupled skyrmion moves from the first region to the second region. The second region is a detection region for performing logic gate operation control. In this way, logic gate operation control can be achieved by driving the movement of the synthetic antiferromagnetic-coupled skyrmion.

[0060] Specifically, a skyrmion is a vortex-like spin magnetic structure, protected by topology, with particle-like characteristics, and its size is only dozens to hundreds of nanometers. Under the combined action of the spin transfer torque generated on the skyrmion by injecting a spin-polarized current, the Magnus force (skyrmion Hall effect) generated during the movement process, and the repulsive force generated by the edge non-uniform magnetic moment, the synthetic antiferromagnetic-coupled skyrmion is driven, and by detecting the presence or absence of the synthetic antiferromagnetic-coupled skyrmion in the second region, logic gate operations can be realized.

[0061] In addition, after the logic gate operation is completed, a driving current in the second direction can be injected into the heavy metal layer, so that the synthetic antiferromagnetic-coupled skyrmion moves from the second region to the first region, that is, the synthetic antiferromagnetic-coupled skyrmion returns to its initial position for the next logical operation, realizing a reversible operation, as Figure 4As shown in the figure, in this way, the generation of skyrmions during each logical operation is avoided, the operation steps are reduced, and the energy consumption of the device is lowered. Moreover, there is no need to use a large current to eliminate the skyrmions, which further simplifies the operation and reduces the energy consumption of the device.

[0062] In this way, in the embodiments of the present invention, first, a logic device based on synthetic antiferromagnetic coupled skyrmions for logical manipulation is adopted. Compared with the logic device based on transistors, the performance of the logic device is greatly improved. Secondly, through the stacked structure of the first ferromagnetic layer, the non-magnetic layer, and the second ferromagnetic layer, synthetic antiferromagnetic coupled skyrmions are formed, eliminating the skyrmion Hall effect during the movement process, thereby avoiding the situation where skyrmions touch the edge of the track and annihilate, enhancing the stability and reliability. In addition, the synthetic antiferromagnetic coupled skyrmions are driven to move towards the second region by the driving current in the first direction to achieve logical gate operation control; and after the logical gate operation is completed, the synthetic antiferromagnetic coupled skyrmions are driven back from the second region to the first region by the driving current in the second direction to achieve reversible operation, reducing the complexity of device design and the energy consumption of the device.

[0063] Among them, considering that the first ferromagnetic layer and the second ferromagnetic layer can generate an antiferromagnetic coupling effect through the non-magnetic layer. Therefore, the thickness of the non-magnetic layer can be adjusted to regulate the strength of the antiferromagnetic coupling.

[0064] Among them, the magnitude of the driving current density is J = 4×10 11 A / m 2 .

[0065] Optionally, the X-shaped structure includes a first input branch and a second input branch located in the first region, a first output branch and a second output branch located in the second region, and a cross branch located between the first region and the second region. The cross branch is respectively connected to the first input branch, the second input branch, the first output branch, and the second output branch;

[0066] One end of the first input branch far from the cross branch is provided with a first input end, one end of the second input branch far from the cross branch is provided with a second input end, and the first input end and the second input end are used to receive the input signals of binary data;

[0067] One end of the first input branch close to the cross branch is provided with a first control end, one end of the second input branch close to the cross branch is provided with a second control end. The first control end is used to control the conduction state between the first input branch and the cross branch according to the input signal corresponding to the first input end, and the second control end is used to control the conduction state between the second input branch and the cross branch according to the input signal corresponding to the second input end;

[0068] One end of the first output branch away from the cross branch is provided with a first output terminal, and one end of the second output branch away from the cross branch is provided with a second output terminal. The first output terminal and the second output terminal are used to detect the arrival state of the synthetic antiferromagnetic coupled skyrmion for performing logic gate operation control.

[0069] In this embodiment, the first region and the second region are respectively the left and right sides of the X-shaped structure. The upper and lower tracks on the left side of the X-shaped structure are respectively the first input branch and the second input branch, and the upper and lower tracks on the right side of the X-shaped structure are respectively the first output branch and the second output branch. The region between the first region and the second region is a common region, that is, a cross branch is provided, so that the cross branch is respectively connected to the first input branch, the second input branch, the first output branch and the second output branch. There are generation regions of synthetic antiferromagnetic coupled skyrmions on the first input branch and the second input branch (i.e., Figure 2 the dotted circular region in the figure).

[0070] One end of the first input branch away from the cross branch is provided with a first input terminal (denoted as input A), and one end of the second input branch away from the cross branch is provided with a second input terminal (denoted as input B). The first input terminal and the second input terminal are used to receive input signals of binary data, such as binary data "1" and "0". One end of the first output branch away from the cross branch is provided with a first output terminal (denoted as output A), and one end of the second output branch away from the cross branch is provided with a second output terminal (denoted as output B). Optionally, the first output terminal is the output terminal of the AND gate "and", and the second output terminal is the output terminal of the OR gate "or". The synthetic antiferromagnetic coupled skyrmion can be detected by using the non-collinear magnetoresistance effect. According to the detection result, that is, the arrival state of the synthetic antiferromagnetic coupled skyrmion, logic gate operation control is performed.

[0071] Specifically, by providing a first control terminal at one end of the first input branch close to the cross branch and a second control terminal at one end of the second input branch close to the cross branch, the first control terminal controls the conduction state of the first input branch and the cross branch according to the input signal corresponding to the first input terminal, and the second control terminal is used for the input signal corresponding to the second input terminal to control the conduction state of the second input branch and the cross branch. In this way, through the design of the X-shaped structure (i.e., the track design) and the control of the moving path of the synthetic antiferromagnetic coupled skyrmion, logic gate operation control is realized by driving the movement of the synthetic antiferromagnetic coupled skyrmion.

[0072] Optionally, the first input branch, the second input branch, the first output branch, and the second output branch are arranged in parallel, and the first input branch and the first output branch are on the same straight line, and the second input branch and the second output branch are on the same straight line;

[0073] Wherein, on the cross branch, the first connection line is perpendicular to the second connection line. The first connection line is the connection line of the first input branch and the second output branch on the cross branch, and the second connection line is the connection line of the second input branch and the first output branch on the cross branch.

[0074] In this embodiment, the four branches of the X-shaped structure in the up, down, left, and right directions are all 50 nm wide and 110 nm long. Each branch deviates from the middle by a length of 40 nm. The first input branch, the second input branch, the first output branch, and the second output branch are arranged in parallel, and the first input branch and the first output branch are on the same straight line, and the second input branch and the second output branch are on the same straight line, so as to facilitate driving the movement of the synthetic antiferromagnetic coupled skyrmion in the first region or the second region. In addition, on the cross branch, the first connection line is perpendicular to the second connection line, so as to facilitate the movement of the synthetic antiferromagnetic coupled skyrmion on the cross branch between the first region and the second region.

[0075] The reversible logic device provided in this embodiment adopts a double-layer racetrack. The synthetic antiferromagnetic coupled skyrmion composed of the first skyrmion and the second skyrmion with opposite polarities is used to represent the binary data "1" and "0" according to the presence or absence of the synthetic antiferromagnetic coupled skyrmion. The logical operation functions of the "AND" gate and the "OR" gate are realized by controlling the movement of the synthetic antiferromagnetic coupled skyrmion.

[0076] The embodiment of the present invention also provides a control method for a reversible logic device, which is applied to the above-mentioned reversible logic device, as Figure 5 shown, the method includes:

[0077] When the synthetic antiferromagnetic coupled skyrmion is generated in the composite structure layer of the reversible logic device, inject a driving current in the first direction into the heavy metal layer;

[0078] The driving current in the first direction injects a spin current into the first ferromagnetic layer through the spin Hall effect in the heavy metal layer, generates a spin transfer torque on the magnetic moment, and the synthetic antiferromagnetic coupled skyrmion moves from the first region towards the second region;

[0079] Perform logical gate operation control according to the arrival state of the synthetic antiferromagnetic coupled skyrmion in the second region;

[0080] After completing the manipulation of the logic gate operation, a driving current in the second direction is injected into the heavy metal layer, so that the synthetic antiferromagnetic coupled skyrmions moving to the second region move towards the first region.

[0081] In this embodiment, first, a logic device based on synthetic antiferromagnetic coupled skyrmions is used for logic manipulation. Compared with the logic device based on transistors, the performance of the logic device is greatly improved. Secondly, through the stacked structure of the first ferromagnetic layer, non-magnetic layer and second ferromagnetic layer, synthetic antiferromagnetic coupled skyrmions are formed. By manipulating the movement of the synthetic antiferromagnetic coupled skyrmions, logical operations are realized, and the skyrmion Hall effect during the movement is eliminated, thus avoiding the situation where skyrmions touch the edge of the track and annihilate, and enhancing the stability and reliability.

[0082] In addition, by injecting a driving current in the first direction into the heavy metal layer, based on the spin Hall effect, a spin current is generated and vertically injected into the first ferromagnetic layer, thereby generating a spin torque on the skyrmions in the first ferromagnetic layer to drive the skyrmions in the first ferromagnetic layer to move from the first region towards the second region; and the corresponding skyrmions in the second ferromagnetic layer move synchronously with the skyrmions in the first ferromagnetic layer under the antiferromagnetic coupling effect. In this way, the driving of the synthetic antiferromagnetic coupled skyrmions towards the second region is realized. The second region is a detection region for logic gate operation manipulation. Furthermore, by driving the movement of the synthetic antiferromagnetic coupled skyrmions, logic gate operation manipulation is realized.

[0083] Moreover, after the logic gate operation is completed, by injecting a driving current in the second direction into the heavy metal layer, based on the same principle as above, the synthetic antiferromagnetic coupled skyrmions return from the second region to the first region, realizing a reversible operation, avoiding generating synthetic antiferromagnetic coupled skyrmions for each logical operation, reducing the operation steps, and lowering the energy consumption of the device; and there is no need to use a large current to clear the synthetic antiferromagnetic coupled skyrmions, further simplifying the operation and reducing the energy consumption of the device.

[0084] Optionally, before injecting the driving current in the first direction into the heavy metal layer, the method further includes:

[0085] Injecting a spin-polarized current into the composite structure layer to generate the synthetic antiferromagnetic coupled skyrmions, where the synthetic antiferromagnetic coupled skyrmions are obtained by antiferromagnetic coupling according to the first skyrmions and the second skyrmions. The first skyrmions are the corresponding skyrmions in the first ferromagnetic layer, and the second skyrmions are the corresponding skyrmions in the second ferromagnetic layer.

[0086] In this embodiment, in the skyrmion generation region (i.e., Figure 2When a spin-polarized current is injected into the composite structure layer from the dashed circular area of the first region), the corresponding skyrmions in the first ferromagnetic layer and the corresponding skyrmions in the second ferromagnetic layer undergo an antiferromagnetic coupling effect to obtain synthetic antiferromagnetic-coupled skyrmions. Since the ferromagnetic skyrmions (i.e., the first skyrmion and the second skyrmion) in the two ferromagnetic layers (i.e., the first ferromagnetic layer and the second ferromagnetic layer) have opposite polarities, after being coupled together through the interlayer antiferromagnetic coupling effect, the directions of the Magnus forces caused by the opposite polarities of the two ferromagnetic skyrmions are opposite and the magnitudes are equal. There is no skyrmion Hall effect during the movement process, that is, it always moves in a straight line along the driving direction and does not deviate from the track, reducing the situation where skyrmions touch the edge of the track and annihilate, and enhancing the stability and reliability.

[0087] Among them, considering that the first ferromagnetic layer and the second ferromagnetic layer can generate an antiferromagnetic coupling effect through a non-magnetic layer. Therefore, the thickness of the non-magnetic layer can be adjusted to regulate the strength of the antiferromagnetic coupling.

[0088] Furthermore, binary data can be used as the signal input. The control terminals on the first input branch and the second input branch can determine whether to use the voltage-controlled magnetic anisotropy effect to change the magnetic crystal anisotropy in the ferromagnetic layer to form a potential barrier according to the input signal, and control the intercommunication between the generation area (i.e., the first input branch and the second input branch corresponding to the first region) and the common area (i.e., the cross branch) of the synthetic antiferromagnetic-coupled skyrmions. Specifically, the following description can be referred to:

[0089] Optionally, the movement of the synthetic antiferromagnetic-coupled skyrmions from the first region towards the second region includes:

[0090] Input binary data "1" to the first input terminal and binary data "1" to the second input terminal;

[0091] The first control terminal controls the conduction state between the first input branch and the cross branch to be open according to the binary data "1" received by the first input terminal, so that the synthetic antiferromagnetic-coupled skyrmions in the first input branch move to the cross branch;

[0092] The second control terminal controls the conduction state between the second input branch and the cross branch to be open according to the binary data "1" received by the second input terminal, so that the synthetic antiferromagnetic-coupled skyrmions in the second input branch move to the cross branch;

[0093] The synthetic antiferromagnetic coupled skyrmions in the first input branch and the synthetic antiferromagnetic coupled skyrmions in the second input branch repel each other in the crossover branch, causing the synthetic antiferromagnetic coupled skyrmions in the first input branch to move to the first output end of the first output branch, and the synthetic antiferromagnetic coupled skyrmions in the second input branch to move to the second output end of the second output branch.

[0094] In one embodiment, as Figure 6 shown, when binary data "1" is input to the first input terminal and binary data "1" is input to the second input terminal, that is, when the logical inputs are "1" and "1", the first control terminal controls the conduction state of the first input branch and the crossover branch to be on, and the second control terminal controls the conduction state of the second input branch and the crossover branch to be on, causing the synthetic antiferromagnetic coupled skyrmions in the first input branch to move to the crossover branch, and the synthetic antiferromagnetic coupled skyrmions in the second input branch to move to the crossover branch;

[0095] The synthetic antiferromagnetic coupled skyrmions in the first input branch and the synthetic antiferromagnetic coupled skyrmions in the second input branch meet in the crossover branch. Due to the mutual repulsion between skyrmions and the action of the driving current in the first direction, the synthetic antiferromagnetic coupled skyrmions in the first input branch (input A) move to the first output end (output A) of the first output branch, and the synthetic antiferromagnetic coupled skyrmions in the second input branch (input B) move to the second output end (output B) of the second output branch. The first output end is the output end of the AND gate, and the second output end is the output end of the OR gate. In this way, skyrmions are detected at output A, realizing the "and" operation of logic A "1" + B "1", that is, the AND operation of "1 + 1 = 1". Skyrmions are detected at output B, realizing the "or" operation of logic A "1" · B "1", that is, the OR operation of "1 · 1 = 1".

[0096] Among them, the conduction state of the control input branch and the crossover branch can be referred to the following description:

[0097] Exemplarily, as Figure 2 shown, a control region can be set at the connection of the input branch and the crossover branch. The control terminal applies a voltage to the control region according to the binary data "0" to generate a potential barrier to prevent the intercommunication of synthetic antiferromagnetic coupled skyrmions between the generation region (i.e., the input branch) and the common region (i.e., the crossover branch); the control terminal does not apply a voltage to the control region according to the binary data "1", allowing the intercommunication of synthetic antiferromagnetic coupled skyrmions between the generation region (i.e., the input branch) and the common region (i.e., the crossover branch).

[0098] Optionally, the movement of the synthetic antiferromagnetic coupled skyrmions from the first region to the second region includes:

[0099] Input binary data "1" to the first input terminal and binary data "0" to the second input terminal;

[0100] Based on the binary data "1" received by the first input terminal, the first control terminal controls the conduction states of the first input branch and the cross branch to be on, so that the synthetic antiferromagnetic coupled skyrmion in the first input branch moves to the cross branch;

[0101] Based on the binary data "0" received by the second input terminal, the second control terminal controls the conduction states of the second input branch and the cross branch to be off, so that the synthetic antiferromagnetic coupled skyrmion in the second input branch cannot move to the cross branch;

[0102] Due to the influence of the chiral property, the synthetic antiferromagnetic coupled skyrmion in the first input branch moves through the cross branch to the second output terminal of the second output branch.

[0103] In one embodiment, as Figure 7 shown, input binary data "1" to the first input terminal and binary data "0" to the second input terminal; that is, when the logical inputs are "1" and "0", the first control terminal controls the conduction states of the first input branch and the cross branch to be on, and the second control terminal controls the conduction states of the second input branch and the cross branch to be off, so that the synthetic antiferromagnetic coupled skyrmion in the first input branch moves to the cross branch, and the synthetic antiferromagnetic coupled skyrmion in the second input branch cannot move to the cross branch;

[0104] Under the influence of the driving current in the first direction and the chiral property of the synthetic antiferromagnetic coupled skyrmion, the synthetic antiferromagnetic coupled skyrmion in the first input branch moves through the cross branch to the second output terminal (Output B) of the second output branch; the synthetic antiferromagnetic coupled skyrmion in the second input branch cannot move to any output terminal. Therefore, no skyrmion can be detected at Output A, realizing the AND operation of "1 + 0 = 0". A skyrmion is detected at Output B, realizing the OR operation of "1 · 0 = 1".

[0105] Optionally, the movement of the synthetic antiferromagnetic coupled skyrmion from the first region towards the second region includes:

[0106] Input binary data "0" to the first input terminal and binary data "1" to the second input terminal;

[0107] Based on the binary data "0" received by the first input terminal, the first control terminal controls the conduction states of the first input branch and the cross branch to be off, so that the synthetic antiferromagnetic coupled skyrmion in the first input branch cannot move to the cross branch;

[0108] The second control terminal controls the conduction state of the second input branch and the cross branch to be on according to the binary data "1" received by the second input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the second input branch moves to the cross branch;

[0109] Due to the influence of the chiral property, the synthetic antiferromagnetic coupled skyrmion in the second input branch moves to the second output terminal of the second output branch through the cross branch.

[0110] In one embodiment, as Figure 8 shown, binary data "0" is input to the first input terminal and binary data "1" is input to the second input terminal; that is, when the logical inputs are "0" and "1", the first control terminal controls the conduction state of the first input branch and the cross branch to be off, and the second control terminal controls the conduction state of the second input branch and the cross branch to be on, so that the synthetic antiferromagnetic coupled skyrmion in the first input branch cannot move to the cross branch, and the synthetic antiferromagnetic coupled skyrmion in the second input branch moves to the cross branch;

[0111] Under the influence of the driving current in the first direction and the chiral property of the synthetic antiferromagnetic coupled skyrmion, the synthetic antiferromagnetic coupled skyrmion in the second input branch moves to the second output terminal (output B) of the second output branch through the cross branch; the synthetic antiferromagnetic coupled skyrmion in the first input branch cannot move to any output terminal. Therefore, no skyrmion can be detected at output A, realizing the AND operation of "0 + 1 = 0". A skyrmion is detected at output B, realizing the OR operation of "0 · 1 = 1".

[0112] Optionally, the movement of the synthetic antiferromagnetic coupled skyrmion from the first region to the second region includes:

[0113] Binary data "0" is input to the first input terminal and binary data "0" is input to the second input terminal;

[0114] The first control terminal controls the conduction state of the first input branch and the cross branch to be off according to the binary data "0" received by the first input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the first input branch cannot move to the cross branch;

[0115] The second control terminal controls the conduction state of the second input branch and the cross branch to be off according to the binary data "0" received by the second input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the second input branch cannot move to the cross branch.

[0116] In one embodiment, as Figure 9As shown, binary data "0" is input to the first input terminal and binary data "0" is input to the second input terminal; that is, when the logical inputs are "0" and "0", the first control terminal controls the conduction states of the first input branch and the cross branch to be closed, and the second control terminal controls the conduction states of the second input branch and the cross branch to be closed, so that the synthetic antiferromagnetic coupled skyrmions in the first input branch cannot move to the cross branch, and the synthetic antiferromagnetic coupled skyrmions in the second input branch cannot move to the cross branch;

[0117] Even under the action of the driving current in the first direction, both the synthetic antiferromagnetic coupled skyrmions in the first input branch and the synthetic antiferromagnetic coupled skyrmions in the second input branch only tend to move towards the second region, but cannot move to the cross branch due to the potential barrier formed by the voltage. Therefore, skyrmions cannot be detected at output A, realizing the AND operation of "0 + 0 = 0". Skyrmions cannot be detected at output B either, realizing the OR operation of "0 · 0 = 0".

[0118] It should be noted that in this article, the terms "including", "comprising" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or further includes elements inherent to such process, method, article or device. Without further limitations, an element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, article or device including that element.

[0119] The embodiments of the present invention have been described above in conjunction with the accompanying drawings, but the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the purpose of the present invention and the scope protected by the claims, and all belong to the protection scope of the present invention.

Claims

1. A reversible logic device, characterized in that, It includes a composite structure layer and a heavy metal layer. The composite structure layer includes a first ferromagnetic layer, a non-magnetic layer, and a second ferromagnetic layer which are sequentially stacked. The heavy metal layer is disposed on one side of the composite structure layer close to the first ferromagnetic layer. The projection of the composite structure layer onto the heavy metal layer coincides with the heavy metal layer. Along the projection direction, the reversible logic device has an X-shaped structure. The input end and the output end of the reversible logic device are respectively located in a first region and a second region, and the first region and the second region are respectively located at opposite ends of the X-shaped structure. The magnetization direction of the first ferromagnetic layer is opposite to that of the second ferromagnetic layer, and both are perpendicular to the non-magnetic layer. A synthetic antiferromagnetic coupled skyrmion is generated in the composite structure layer, and the synthetic antiferromagnetic coupled skyrmion is generated by injecting a spin-polarized current into the composite structure layer. Wherein, when a driving current in a first direction is injected into the heavy metal layer, the synthetic antiferromagnetic coupled skyrmion moves from the first region towards the second region. When a driving current in a second direction is injected into the heavy metal layer, the synthetic antiferromagnetic coupled skyrmion moves from the second region towards the first region. The first direction is opposite to the second direction. The first region is the generation region of the synthetic antiferromagnetic coupled skyrmion, and the second region is the detection region for performing logic gate operation control.

2. The reversible logic device according to claim 1, characterized in that, The X-shaped structure includes a first input branch and a second input branch located in the first region, a first output branch and a second output branch located in the second region, and a cross branch located between the first region and the second region. The cross branch is respectively connected to the first input branch, the second input branch, the first output branch, and the second output branch. One end of the first input branch away from the cross branch is provided with a first input end, and one end of the second input branch away from the cross branch is provided with a second input end. The first input end and the second input end are used to receive input signals of binary data. One end of the first input branch close to the cross branch is provided with a first control end, and one end of the second input branch close to the cross branch is provided with a second control end. The first control end is used to control the conduction state between the first input branch and the cross branch according to the input signal corresponding to the first input end, and the second control end is used to control the conduction state between the second input branch and the cross branch according to the input signal corresponding to the second input end. One end of the first output branch away from the cross branch is provided with a first output end, and one end of the second output branch away from the cross branch is provided with a second output end. The first output end and the second output end are used to detect the arrival state of the synthetic antiferromagnetic coupled skyrmion for performing logic gate operation control.

3. The reversible logic device according to claim 2, wherein The first output end is the output end of an AND gate, and the second output end is the output end of an OR gate.

4. The reversible logic device according to claim 2, wherein The first input branch, the second input branch, the first output branch, and the second output branch are arranged in parallel, and the first input branch and the first output branch are on the same straight line, and the second input branch and the second output branch are on the same straight line; Wherein, on the cross branch, the first connection line is perpendicular to the second connection line. The first connection line is the connection line of the first input branch and the second output branch on the cross branch, and the second connection line is the connection line of the second input branch and the first output branch on the cross branch.

5. A control method for a reversible logic device, characterized in that, Applied to the reversible logic device according to any one of claims 1 to 4, the method includes: When the synthetic antiferromagnetic coupled skyrmion is generated in the composite structure layer of the reversible logic device, inject a driving current in a first direction into the heavy metal layer; The driving current in the first direction injects a spin current into the first ferromagnetic layer through the spin Hall effect in the heavy metal layer, generates a spin transfer torque on the magnetic moment, and the synthetic antiferromagnetic coupled skyrmion moves from the first region to the second region; Perform logic gate operation control according to the arrival state of the synthetic antiferromagnetic coupled skyrmion in the second region; After completing the logic gate operation control, inject a driving current in a second direction into the heavy metal layer to make the synthetic antiferromagnetic coupled skyrmion moved to the second region move towards the first region.

6. The method according to claim 5, wherein Before injecting the driving current in the first direction into the heavy metal layer, the method further includes: Inject a spin-polarized current into the composite structure layer to generate the synthetic antiferromagnetic coupled skyrmion, wherein the synthetic antiferromagnetic coupled skyrmion is obtained by antiferromagnetic coupling according to a first skyrmion and a second skyrmion. The first skyrmion is the corresponding skyrmion in the first ferromagnetic layer, and the second skyrmion is the corresponding skyrmion in the second ferromagnetic layer.

7. The method according to claim 5, wherein The movement of the synthetic antiferromagnetic coupled skyrmion from the first region to the second region includes: Input binary data "1" to the first input terminal and binary data "1" to the second input terminal; The first control terminal controls the conduction state of the first input branch and the cross branch to be open according to the binary data "1" received by the first input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the first input branch moves to the cross branch; The second control terminal controls the conduction state of the second input branch and the cross branch to be open according to the binary data "1" received by the second input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the second input branch moves to the cross branch; The synthetic antiferromagnetic coupled skyrmion in the first input branch and the synthetic antiferromagnetic coupled skyrmion in the second input branch repel each other in the cross branch, so that the synthetic antiferromagnetic coupled skyrmion in the first input branch moves to the first output terminal of the first output branch, and the synthetic antiferromagnetic coupled skyrmion in the second input branch moves to the second output terminal of the second output branch.

8. The method according to claim 5, characterized in that, The synthetic antiferromagnetic coupled skyrmion moves from the first region towards the second region, including: Input binary data "1" to the first input terminal and binary data "0" to the second input terminal; The first control terminal controls the conduction state of the first input branch and the cross branch to be on according to the binary data "1" received by the first input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the first input branch moves to the cross branch; The second control terminal controls the conduction state of the second input branch and the cross branch to be off according to the binary data "0" received by the second input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the second input branch cannot move to the cross branch; Due to the influence of the chiral property, the synthetic antiferromagnetic coupled skyrmion in the first input branch moves through the cross branch to the second output terminal of the second output branch.

9. The method according to claim 5, wherein The synthetic antiferromagnetic coupled skyrmion moves from the first region towards the second region, including: Input binary data "0" to the first input terminal and binary data "1" to the second input terminal; The first control terminal controls the conduction state of the first input branch and the cross branch to be off according to the binary data "0" received by the first input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the first input branch cannot move to the cross branch; The second control terminal controls the conduction state of the second input branch and the cross branch to be on according to the binary data "1" received by the second input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the second input branch moves to the cross branch; Due to the influence of the chiral property, the synthetic antiferromagnetic coupled skyrmion in the second input branch moves through the cross branch to the second output terminal of the second output branch.

10. The method according to claim 5, wherein The synthetic antiferromagnetic coupled skyrmion moves from the first region towards the second region, including: Input binary data "0" to the first input terminal and binary data "0" to the second input terminal; The first control terminal controls the conduction state of the first input branch and the cross branch to be off according to the binary data "0" received by the first input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the first input branch cannot move to the cross branch; The second control terminal controls the conduction state of the second input branch and the cross branch to be off according to the binary data "0" received by the second input terminal, so that the synthetic antiferromagnetic coupled skyrmion in the second input branch cannot move to the cross branch.

Images