50 results about "Dilution refrigerator" patented technology

The invention relates to the technical field of dilution refrigerators, in particular to a liquid-helium-free dilution refrigerator with a rapid precooling inner cavity structure, which comprises a first rack and a second rack, a top plate is fixedly mounted at the top of the second rack, a top cover is fixedly arranged on the top plate, and a shell assembly is fixedly mounted at the bottom of the top cover. A multi-layer vacuum cavity assembly used for providing a vacuum environment is arranged in the shell assembly, a dilution refrigeration unit and an inner cavity mechanism assembly are arranged on the multi-layer vacuum cavity assembly, and the inner cavity mechanism assembly, the top cover and the multi-layer vacuum cavity assembly are jointly provided with an adjustable inflation and deflation mechanism used for adjusting an air inlet and outlet mode. Through cooperative use of the driving mechanism and the step-by-step regulation and control assembly in the adjustable inflation and deflation mechanism, switching of air inlet and outlet modes is achieved, mode switching of air inlet and outlet through a single through hole and simultaneous air inlet and outlet through multiple vent holes is achieved, and different working modes can be conveniently switched according to actual needs.

Inside the vacuum enclosure (101) of a cryostat, a plurality of temperature stages form an ordered series in a primary direction. They are cooled to respective cryogenically cooled temperatures with stages (104, 106) of a staged cooling system. A first dilution refrigerator (1001) comprises a first still (109) and a first mixing chamber (110), of which said first still (109) is located on a first still flange (501) and said first mixing chamber (110) is located on a first mixing chamber flange (502). A second dilution refrigerator (1002) comprises a second still (301) and a second mixing chamber (302), of which said second still (301) is located on a second still flange (504) and said second mixing chamber (302) is located on a second mixing chamber flange (505). Said first still flange (501) is thermally separate from said second still flange (504). Said first mixing chamber flange (502) is thermally separate from said second mixing chamber flange (505). Said second dilution refrigerator (1002) is configured for a larger cooling power than said first dilution refrigerator (1001).

Provided herein are systems and methods for improved thermalization of a dilution refrigerator. The dilution refrigerator includes a still, a mixing chamber, a first continuous heat exchanger, and a second continuous heat exchanger. The continuous heat exchangers are disposed between the mixing chamber and the still, and an intermediate cold plate is disposed between the first continuous heat exchanger and the second continuous heat exchanger. An outgoing flow path of fluid helium from the mixing chamber to the still is thermalized to the intermediate cold plate.

This invention relates to a double-helix continuous variable-diameter shell-and-tube heat exchanger for a dilution refrigerator and its manufacturing method. The heat exchanger comprises a central inner tube and an outer tube, serving as a pre-stage heat exchanger for a separate silver powder sintered heat exchanger in the dilution refrigerator. The dense-phase fluid of the dilution refrigerator flows in the cooling direction within the central inner tube, while the dilute-phase fluid flows in the heating direction within the annular gap between the outer tube and the central inner tube. The central inner tube has a spring-shaped primary helical structure, coaxially inserted into the inner cavity of the outer tube. The inserted central inner tube and outer tube together form a secondary helix, creating a nested double-helix structure. In the cooling flow direction of the dense-phase fluid, the central inner tube is divided into an integrally formed constant-diameter section and a non-linearly expanding section. The outer tube is a seamless tube with a constant inner diameter throughout. This invention also includes a method. This invention significantly increases the heat exchange area within a compact space, thereby achieving efficient counter-current heat exchange, while reducing parasitic heat in the extremely low temperature region and providing some protection for the downstream separate heat exchanger, effectively improving the overall performance of the dilution refrigerator.

The utility model provides a temperature sensing unit and a detection device. The temperature sensing unit comprises a magnetic material, an antenna substrate, a diamond, a condensing lens, an optical filter, a photoelectric detector and a laser output port. According to the scheme, on the basis of the principle that the magnetic field of the magnetic material can change along with the temperature, the temperature is reversely deduced by measuring the magnetic field change of the magnetic material through the diamond NV color center, and due to the fact that the magnetic field detection sensitivity of the diamond NV color center is extremely high, higher temperature measurement sensitivity can be obtained in a wide temperature range through temperature inversion through the scheme. Meanwhile, the utility model provides a detection device suitable for monitoring the temperature of the cold plate of the dilution refrigerator, and the application feasibility of the NV color center sensing technology in the field is verified.

The utility model relates to the field of dilution refrigerators, in particular to a heat exchange structure for a dilution refrigerator, which comprises a heat exchange mechanism, an upper seal cover is fixedly mounted on the upper side of the heat exchange mechanism, and a lower seal cover is fixedly mounted on the lower side of the heat exchange mechanism. The heat exchange mechanism comprises a heat exchange assembly, the heat exchange assembly comprises a heat exchanger body, and a first connecting pipe is fixedly installed at the position, close to the middle, of the upper end of the heat exchanger body; due to the fact that the first flow guide groove and the second flow guide groove which are in the reverse spiral shape are designed, the heat exchange area is greatly increased, cold fluid and hot fluid can make full contact in the flowing process, and therefore the heat exchange efficiency is improved. Due to the reverse spiral design, the heat exchange efficiency is improved, the space is effectively saved, in the same volume, the spiral flow guide groove can provide a longer flowing path and a larger heat exchange area, and therefore double optimization of efficient heat exchange and space utilization is achieved.

A dilution refrigerator comprises: a separator (50) that is disposed below a mixer (10) and separates helium-3 from a mixed liquid; a heat exchange unit (60) that is disposed between the mixer (10) and the separator (50), forms a counter flow between a dense phase mixed liquid which rises from the separator (50) to the mixer (10) and a dilute phase mixed liquid which flows down from the mixer (10) to the separator (50), and performs heat exchange between the dense phase mixed liquid and the dilute phase mixed liquid by means of the counter flow; a helium-4 circulation unit (40) that comprises a filter for separating helium-4 from the mixed liquid, separates the helium-4 from the dilute phase mixed liquid in the separator (50) by using the mechanocaloric effect, and returns the helium-4 to the dilute phase mixed liquid in the mixer (10); and an auxiliary refrigerator that achieves low temperature by means of reduced-pressure discharge of the helium-3. The auxiliary refrigerator cools the helium-4 which is returned to the mixer (10) by the helium-4 circulation unit (40).

The invention discloses a loop differential thermal expansion combined air gap type thermal switch for a dilution refrigerator and a manufacturing method of the loop differential thermal expansion combined air gap type thermal switch for the dilution refrigerator. The device is composed of a cold-end base, a hot-end base, a supporting shell, a cold-end conductor, a hot-end conductor, a concentric staggered cold-end cylinder group and a concentric staggered hot-end cylinder group. By means of the structural arrangement and the difference of thermal expansion coefficients of different materials, extremely small air gaps are naturally formed between conductors at low temperature, and harsh machining precision is not needed. Meanwhile, the design of the concentric staggered cylinder group greatly increases the heat exchange area, so that the heat exchange efficiency of the gas working medium is enhanced; high-reliability sealing is realized by adopting a sealing structure of an annular sealing groove and a high-purity indium wire, and an initial gap is ensured to be adjustable by matching with bolt pretightening force control. And positive significance is achieved on performance improvement and production and manufacturing of the dilution refrigerating machine.

The application provides a volume measuring device and a volume measuring method of a heat exchanger of a dilution refrigerator, and relates to the technical fields of volume measurement and dilution refrigerator. The volume measuring device comprises a reference container, a pressure regulating assembly, a first valve and a pressure gauge. The reference container is used for connecting a to-be-measured container and has a first cylinder and a second cylinder which are slidably connected with each other, and the second cylinder is suitable for reciprocally sliding relative to the first cylinder in an axial direction to change the volume of the reference container. The pressure gauge is suitable for measuring the internal pressure of the reference container. The first valve is arranged between the reference container and the to-be-measured container. The pressure regulating assembly adjusts the pressure in the reference container and the to-be-measured container to a reference pressure and closes the first valve in response to the first valve being initially opened; then adjusts the pressure of the reference container to a first pressure and opens the first valve again, so that the pressure gauge reading decreases to a second pressure; and then drives the second cylinder to slide towards the first cylinder until the pressure gauge reading returns to the first pressure.

The invention discloses a vibration isolation unit, a cryostat, a dilution refrigerator and a processing method of the vibration isolation unit. The vibration isolation unit comprises a first connecting line, and the first connecting line is connected with the interior of the cryostat and a cable winding and unwinding device; the spring element is connected with the connecting line I; the second connecting line is connected with the spring element. The cryostat comprises a pulse tube refrigeration unit. The lower part of the pulse tube refrigerator is connected with a cooling disc unit; the dilution refrigerator includes a cryostat. The processing method comprises the steps of determining vibration parameters received by the dilution refrigerator, determining a vibration isolation target of the vibration isolation unit, and solving parameters of the vibration isolation unit. The vibration isolation unit is connected with the quantum chip, so that the quantum chip unit is not in direct contact with the multi-stage cold disc unit, the quantum chip unit is in a suspended state and is only connected with the vibration isolation unit, and mechanical vibration caused by the pulse tube refrigerator and environmental factors can be effectively isolated.

Systems and methods for improving the performance of dilution refrigeration systems are described. Filters and traps employed in the helium circuit of a dilution refrigerator may be modified to improve performance. Some traps may be designed to harness cryocondensation as opposed to cryoadsorption. A cryocondensation trap employs a cryocondensation surface having a high thermal conductivity and a high specific heat with a binding energy that preferably matches at least one contaminant but does not match helium. Multiple traps may be coupled in series in the helium circuit, with each trap designed to trap a specific contaminant or set of contaminants. Both cryocondensation and cryoadsorption may be exploited among multiple traps.

A distributed refrigeration system is provided. The distributed refrigeration system comprises a pre-cooling system configured to be thermally coupled to two or more cryogenic devices and to provide a first cooling stage to the two or more cryogenic devices. The two or more cryogenic devices may be two or more of a dilution refrigerator, a low-temperature microscopy system, a 3He refrigeration system, and / or a superconducting CMOS system.

The application discloses a dilution refrigerator vibration isolation device suitable for a multi-vibration source environment and particularly relates to the field of refrigeration and cryogenic engineering, and comprises a flexible vibration isolation structure, a mechanical refrigerator vibration isolation structure, a low-temperature thermostat overall vibration isolation frame and a vibration isolation structure of external auxiliary equipment, the low-temperature thermostat overall vibration isolation frame comprises a cross support reinforced frame, the top of the cross support reinforced frame is provided with a low-temperature thermostat support plate, and air damping pads are arranged between the four corners of the low-temperature thermostat support plate and the top surface of the cross support reinforced frame; and the flexible vibration isolation structure is arranged between a mechanical refrigerator cold head and a dilution refrigerator cold plate. The application can effectively isolate multi-source mechanical vibration interference, improve the operation stability and measurement accuracy of a dilution refrigerator low-temperature thermostat, and ensure the smooth and effective operation of important applications, such as quantum computing and extremely low-temperature physical experiments, which require extremely low external interference.

The application discloses a controllable filling method and system for a helium mixture of a dilution refrigerator, and relates to the technical field of image processing and intelligent control, and comprises the following steps: collecting an image of an outer wall of a target thin tube section to generate a frost band enhanced profile; extracting a half-height width and an edge gradient to calculate a frost band shape anomaly ratio, and generating a throttling influence coefficient according to the frost band shape anomaly ratio; collecting pressure and temperature of a metering cavity to calculate a metering release molar quantity, and correcting the metering release molar quantity by using the throttling influence coefficient to obtain an effective inlet molar quantity; and generating a valve control instruction based on the effective inlet molar quantity. The application can improve the metering accuracy and safety of the filling process.

The present application relates to dilution refrigerator temperature calibration technical field, and disclose a kind of dilution refrigerator thermometer in situ calibration system based on natural cooling dynamics, comprising: according to the dynamics equation of cooling power and temperature Curvature is calculated, according to the temperature corresponding to thermometer resistance value, the temperature is substituted into temperature curvature, and the calibration function of resistance value and temperature is obtained;Identify the multivalued region of temperature, and evolve multiple branch functions in multivalued region in calibration function, calculate the deviation measure of each branch function and calibration function;In multivalued region, the support degree of each branch function to calibration function is calculated, and real-time data is obtained by adjusting calculation load, to minimize the number of experiments to verify calibration function;According to the branch verification result of multivalued region, dynamically adjust the verification strategy of non-multivalued region, under the premise of not relaxing calibration accuracy, through dynamics branch and load guide, significantly reduce the repeated experiment cost of dilution refrigerator cryogenic calibration.

Disclosed is a still chamber for a dilution refrigerator. The still chamber comprises a base region for accommodating a liquid mixture of helium-3 and helium-4, an outlet for directing helium vapor evaporated from the liquid mixture into a still pumping line and one or more cooling elements between the base region and the outlet for recondensing helium-4 from the helium vapor.

The invention discloses a material mechanical property testing device and method. The device comprises a clamping module, a load execution module, a displacement measurement module and a control module. The method comprises the following steps: mounting the material mechanical property testing device on a cold disc of a dilution refrigerator; starting a dilution refrigerator; fixing a to-be-tested sample on the clamping module, and adjusting the posture of the sample; in an extremely low temperature environment, the control module controls the power module to drive a pressure head of the load execution module to execute micro-impact press-in action on a to-be-tested sample at a preset impact speed; in the impact process, impact load data are synchronously collected, and displacement data of a pressure head are synchronously collected through a displacement measurement module; based on the collected impact load data and displacement data, the control module calculates mechanical property parameters of the to-be-tested sample in the extremely low temperature environment. According to the invention, the problem of temperature lower limit and medium interference caused by traditional liquid helium infiltration or circulating refrigeration can be effectively avoided, and the mechanical property test can be executed at extremely low temperature.

The invention discloses a rapid cooling dilution unit. The rapid cooling dilution unit comprises a dilution unit inlet, a closed heat exchange structure and a dilution unit outlet, the closed heat exchange structure comprises an upper base plate, an inflation and deflation opening, a lower base plate, a dilution cavity, a heat exchanger set, a sealing wall face, a heating device and an adsorption device. The upper base plate, the lower base plate and the sealing wall face form a sealing cavity, the heat exchanger set is arranged in the sealing cavity, and pipelines in the heat exchanger set are connected with the dilution unit inlet, the dilution unit outlet and the dilution cavity in a sealed mode to form a circulating heat exchange pipeline. The inflation and deflation port is formed in the sealing cavity; the adsorption device is communicated with the interior of the sealed cavity and is filled with an adsorbent; the heating device is arranged on the adsorption device and is used for heating the adsorption device and the adsorbent in the adsorption device. The heat exchanger set is arranged in the sealing cavity, the heat exchange state is regulated and controlled by releasing and adsorbing gas, the cooling efficiency of the dilution refrigeration system is remarkably improved, and meanwhile the heat insulation performance of the dilution refrigeration system in a low-temperature steady state is ensured.

A cold storage material according to an embodiment comprises: a rare earth oxysulfide including a rare earth element; a garnet-type rare earth oxide including a rare earth element and Al; and aluminum oxide, wherein the ratio of an X-ray diffraction peak intensity of the garnet-type rare earth oxide to an X-ray diffraction peak intensity of the rare earth oxysulfide is 0.1% to 40%.

A microfluidic dilution refrigerator comprising a microfluidic system including a mixing chamber, wherein helium-3 dissolves in helium-4 to form a mixture absorbing heat, thereby cooling a device in thermal contact with the mixing chamber; a still wherein the helium-3 in the mixture evaporates from the mixture; and a heat exchanger thermally coupled to the still. The system further comprises a first microfluidic channel guiding the helium-3 from the heat exchanger to the mixing chamber, the first microfluidic channel dimensioned to control flow rate of the helium-3 into the mixing chamber; and a second microfluidic channel guiding the mixture from the mixing chamber to the still. A pumping system is provided for circulating the helium-3 from the still and back into the mixing chamber via the heat exchanger. Devices cooled by the MDR include a quantum sensor or a quantum processor in a quantum computer for performing operations on a qubit.

This invention provides a heat exchanger for a dilution refrigerator, a manufacturing method thereof, and the dilution refrigerator itself, relating to the field of dilution refrigerator technology. The heat exchanger includes multiple sequentially connected heat exchange units, each unit comprising a heat-conducting element, two covers, and a filling material. The two covers are respectively disposed on both sides of the heat-conducting element to define a first chamber and a second chamber. A flow-through flow mechanism is present in the first chamber. 3 He solution, with flow in the second chamber. 3 He solution and 4 A mixture of He solutions, to make 3 The He solution and the mixture exchange heat through a heat-conducting element. A packing material is disposed in the first and second chambers, and a first pore system is formed inside the packing material to facilitate the increase of heat exchange. 3 The heat exchange area between the He solution and the mixture is increased. A second pore system is also formed inside the packing, which is suitable for increasing the heat exchange area while simultaneously increasing... 3 The depth to which He solution and mixture penetrate into the interior of the filler.

The invention discloses a low-vibration desktop type liquid-helium-free dilution refrigerator, which is characterized in that a DR dilution unit and a pulse tube refrigerator are respectively arranged in two mutually independent vacuum containers, and the vacuum containers are connected through a corrugated pipe; and mechanical decoupling between the two is realized. In addition, the DR dilution unit is connected with an air extractor outside the vacuum container; the pulse tube refrigerator is connected with a compressor outside the vacuum container; the high vibration device is separated from the DR dilution unit and the pulse tube refrigerator, so that a vibration source can be effectively isolated, and the vibration reduction effect is improved. A small part of helium is shunted from a helium circulation loop of the pulse tube refrigerator, and the shunted helium cooling loop is connected with the radiation shielding layer after being pre-cooled for multiple times so as to cool the radiation shielding layer; mixed gas in the dilution refrigeration loop enters the DR dilution unit after being pre-cooled for multiple times, deep refrigeration is conducted on a mixing chamber of the dilution unit, and thermal coupling between the DR dilution unit and the mixing chamber is achieved. The low-vibration desktop type dilution refrigerator can be suitable for low-temperature experimental equipment sensitive to vibration, such as STM and AFM.

The utility model provides a temperature sensing probe and a refrigerator cold plate temperature sensing device, comprising an optical fiber probe, a probe fixing member and a microwave antenna, the temperature sensing probe is mainly suitable for application scenarios needing to measure sample shell temperature, such as refrigerator cold plate, chip surface temperature and the like; through the structural design of the optical fiber probe and the probe fixing piece, the diamond block containing the NV color center can be in sufficient and stable contact with the sample to be detected, and it is guaranteed that the temperature detection process is effectively implemented. Meanwhile, the utility model provides temperature sensing equipment suitable for monitoring the temperature of the cold plate of the dilution refrigerator, and the application feasibility of the NV color center sensing technology in the field is verified.

The application discloses a multifunctional integrated gas control system for a dilution refrigerator, and particularly relates to the field of refrigeration and cryogenics, and comprises a liquid nitrogen cold trap, a gas buffer tank, an integrated valve box, a dilution refrigeration inner circulation pipeline, a diaphragm compressor, a Roots pump, a turbo molecular pump and a vacuum pumping pump group. The system uses a highly integrated valve box module, which is responsible for gas path control in different stages such as starting, running, stopping and rewarming of the dilution refrigeration cycle; the application optimizes the flow conductance of the gas path in different temperature zones and under different pressures, reduces heat loss, and ensures high airtightness in the whole temperature zone from room temperature to extremely low temperature, thereby improving the reliability and automation degree of the dilution refrigerator and having a very positive significance for practical application of the dilution refrigeration system.

The utility model discloses an integrated device, a dilution refrigerator and a quantum computer, and the integrated device comprises a first integrated part which is parallel to a cold disc, and a plurality of first electronic devices are integrated on the first integrated part; the second integrated parts are arranged perpendicular to the cold disc, one end of each second integrated part is fixed to the cold disc, the other end of each second integrated part is fixed to the first integrated part, and a plurality of second electronic devices arranged in the height direction of the second integrated parts are integrated on the second integrated parts; one end of the heat conduction column is mounted on the cold disc, and the other end penetrates through the first integrated part to be connected with the quantum chip. The integrated device has the advantages of being efficient in heat dissipation performance, high in integration level and space utilization rate, convenient to wire and the like.

The invention discloses a dry-type cold trap for a dilution refrigerator system, and relates to the technical field of dry-type cold traps. The dry cold trap comprises a vacuum cavity, a temperature control unit and a gas treatment unit. A gas treatment unit is arranged in the vacuum cavity; and the temperature control unit is arranged in the vacuum cavity, is adjacent to the gas treatment unit and provides adjustable temperature. The temperature control unit comprises a refrigeration module, a heat switch, a heat exchange module and a heating module. The refrigeration module is arranged at the bottom of the interior of the vacuum cavity and provides the temperature of a refrigeration range, and the highest temperature of the refrigeration range is at least lower than the boiling point value of the liquid nitrogen; one end of the thermal switch is connected with the refrigeration module; the heat exchange module is connected with the other end of the heat switch and is further in heat connection with the gas treatment unit; and the heating module is thermally connected with the heat exchange module. The dry-type cold trap is simple and convenient to operate.

Provided in the present invention are a superconductor-based coaxial cable of a dilution refrigerator, a dilution refrigerator, and a superconducting quantum computing device. The dilution refrigerator comprises at least a first temperature layer, a second temperature layer, a third temperature layer and a fourth temperature layer. The coaxial cable comprises a conductor layer, an insulating layer and a first shielding layer, the first shielding layer being arranged on the insulating layer at a first thickness. The coaxial cable further comprises a first coaxial cable segment disposed in the first temperature layer, a second coaxial cable segment disposed in the second temperature layer, a third coaxial cable segment disposed in the third temperature layer, and a fourth coaxial cable segment disposed in the fourth temperature layer, wherein the first thickness and the material of the parts of the first shielding layer at the first coaxial cable segment, the second coaxial cable segment, the third coaxial cable segment and the fourth coaxial cable segment are determined on the basis of a preset combination method.

A distributed refrigeration system is provided. The distributed refrigeration system comprises a pre-cooling system configured to be thermally coupled to two or more cryogenic devices and to provide a first cooling stage to the two or more cryogenic devices. The two or more cryogenic devices may be two or more of a dilution refrigerator, a low-temperature microscopy system, a 3He refrigeration system, and / or a superconducting CMOS system.

The application discloses a multi-stage cold accumulation type dilution refrigerator system, which comprises a gas circuit, a refrigeration part and a cold accumulation part. The gas circuit comprises an air inlet pipeline and an air extraction pipeline. The refrigeration part pre-cools working gas in the gas circuit to a target temperature interval. The refrigeration part comprises a cold head room temperature part, a first-stage cold head and a second-stage cold head. One end of the first-stage cold head is connected with the cold head room temperature part and is in thermal connection with the air inlet pipeline. The second-stage cold head is connected with the other end of the first-stage cold head. The cold accumulation part is in thermal connection with the air inlet pipeline, and the cold accumulation part maintains the working gas in the target temperature interval. The cold accumulation part comprises at least two cold accumulation assemblies. Each cold accumulation assembly comprises a cold disc and a cold accumulator. The cold accumulator is fixedly connected with the surface of the cold disc, the cold accumulator is filled with a cold accumulation material, and the cold accumulation material is a solid.

The invention relates to the technical field of extremely-low-temperature refrigeration, and provides a cooling capacity adjustable heat exchanger which comprises a base body, and a mounting cavity is formed in the base body in a sunken mode; the main heat exchange assembly is provided with a central shaft fixedly arranged at the central position of the mounting cavity; a plurality of layers of heat exchange plates are fixedly connected to the central shaft in a penetrating manner, and cake-shaped heat exchange layers are formed on the two sides of each heat exchange plate; and the first auxiliary heat exchange assembly and / or the second auxiliary heat exchange assembly are / is fixedly arranged in an area between the main heat exchange assembly and the inner side wall of the mounting cavity. Therefore, the auxiliary heat exchange assembly is installed in the area around the main heat exchange assembly, the space utilization rate is increased, and the refrigeration efficiency of the heat exchanger is improved. Meanwhile, the first auxiliary heat exchange assembly and the second auxiliary heat exchange assembly can be selectively installed according to needs, so that the overall refrigerating capacity of the heat exchanger is adjustable. And the auxiliary heat exchange assembly occupies the space of the mounting cavity, the using amount of helium is also reduced, and the operation cost is reduced. The invention further provides a dilution refrigerator.