Devices, systems, methods, and computer-implemented methods to facilitate employing thermalizing materials in an enclosure for quantum computing devices are provided. According to an embodiment, a system can comprise a quantum computing device and an enclosure having the quantum computing device disposed within the enclosure. The system can further comprise a thermalizing material disposed within the enclosure, with the thermalizing material being adapted to thermally link a cryogenic device to the quantum computing device.

A heat transfer device includes a storage chamber, a coolant housed within the storage chamber, a cooling chamber, one or more heat transfer components, a fluid passage between the storage chamber and the cooling chamber, and a barrier element. The one or more heat transfer components facilitate heat transfer from a heat source outside of the cooling chamber to the cooling chamber. The barrier element may have (i) a closed configuration, and (ii) an open configuration in which the barrier element is configured to allow the coolant in the storage chamber to flow from the storage chamber into the cooling chamber. The barrier element may reconfigure from the closed configuration to the open configuration in response to a trigger condition, such as the coolant housed within the storage chamber reaching a trigger temperature and/or the initial pressure of the coolant housed within the storage chamber reaching a trigger pressure.

A system for improving an electrical conductivity and reducing an electrical energy loss in an electrical component, the system includes a temperature sensor, insulation for enclosing the electrical component and the temperature sensor, a cooling source to be coupled to the electrical component through the insulation, and a computer connected to the cooling source and the temperature sensor, where the computer is configured to control the cooling source to cool the electrical component to a user-definable temperature as indicated by the temperature sensor and maintain the electrical component at the user-definable temperature for a user-definable period of time.

A system includes a heat exchanger mounted to the brackets and receiving cryogen, the heat exchanger having a vertical inlet coupled in parallel to a plurality of equal size horizontal tubes each traversing a width of the heat exchanger and further coupled in parallel to a vertical outlet pipe with an outlet diameter at least twice an inlet tube diameter; a temperature sensor; a thermostat that monitors the temperature sensor and maintains a predetermined temperature set point by communicating with a solenoid valve coupled to the heat exchanger; an exhaust line coupled to the outlet pipe that expels exhaust gas outside the enclosed facility; multiple fans attached to the heat exchanger; and a fail-safe oxygen sensor to protect a biological object in the enclosed facility.

Use of cryogenic fuel tanks for the cooling of power electronics circuits to improve cooling capabilities for power electronics in vehicles or an aircraft. The power electronics circuit can be cooled via a cryogenic cooling loop by the fuel directly, or the fuel is used to cool a separated coolant tank. A control valve controls the coolant flow within the cryogenic cooling loop based on an electrical property of the power switching element of the power electronics circuit and or based on the way the power switching elements are electrically connected together. The control valve can control the coolant flow such that a junction temperature is achieved which minimizes the drain-source resistance.

A cryogenic cooling system for use in quantum computing applications can include a plurality of cryogenic cooling stages. Each of the plurality of cryogenic cooling stages can include a plurality of interleaved cooling units. The plurality of interleaved cooling units can include a first cooling unit and a second cooling unit. Each of the plurality of interleaved cooling units can have an associated operating temperature range. One or more signal lines that couple one or more classical processors to one or more quantum systems can pass through each of the plurality of interleaved cooling units for each of the plurality of cryogenic cooling stages.

A method and apparatus for cooling a load using liquid nitrogen conveyed in a circuit are provided. Cooled liquid nitrogen is used for cooling the liquid nitrogen conveyed in the circuit. A first proportion of the liquid nitrogen is cooled in an open cooling system and a second proportion is cooled in a closed cooling system using one or more cooling units. The open cooling system and closed cooling system are used for cooling of a power supply having a first end and a second end. The open cooling system is arranged at the first end and the closed cooling system is arranged at the second end. Cooling power is provided in a first time period as a first, smaller amount of total cooling power and in a second time period as a second, higher amount of total cooling power. A first proportion of the amount of total cooling power is provided by means of the open cooling system and a second proportion is provided by means of the closed cooling system. The first proportion in the first time period is set to a lower value than in the second time period.

A cryogenic cooling apparatus includes: a vacuum container; a first bellows connected to a peripheral portion of an opening provided in the vacuum container; a flange provided at a tip of the first bellows on a side opposite to the opening of the vacuum container and configured to fix a refrigerator; a first sleeve connected to a peripheral edge portion of an opening of the flange, into which the refrigerator is inserted, and configured to form a first accommodation space; a first heat-transfer block provided at a tip of the first sleeve on a side opposite to the flange and thermally connected to the first cooling object by being brought into contact with a first cooling block of the refrigerator; and a second bellows formed in a part of the first sleeve and configured to expand or contract the accommodation space depending on the refrigerator inserted into the accommodation space.

Systems and methods that employ interactions between quantum computing systems and digital computing systems are described. For an iterative method, a quantum computing system may be designed, operated, and/or adapted to provide a rate of convergence that is greater than the rate of convergence of a digital supercomputer. When the digital supercomputer is iteratively used to evaluate an objective function at a cost incurred of C per iteration, the quantum computing system may be used to provide the input parameter(s) to the objective function and quickly converge on the input parameter(s) that optimize the objective function. Thus, a quantum computing system may be used to minimize the total cost incurred C.sub.T for consumption of digital supercomputer resources when a digital supercomputer is iteratively employed to evaluate an objective function.

The embodiments herein describe technologies of cryogenic digital systems with a first component located in a first non-cryogenic temperature domain, a second component located in a second temperature domain that is lower in temperature than the first cryogenic temperature domain, and a third component located in a cryogenic temperature domain that is lower in temperature than the second cryogenic temperature domain.