This chapter reviews various methods and their operating principles for producing cryogenic temperatures. The use of liquid cryogens for laboratory studies of superconducting electronic devices is a common practice. That technique is mentioned briefly but the major focus of this chapter is on the use of closed-cycle cryocoolers for most practical applications of superconductingdevices. The primary closed-cycle methods discussed are the Joule-Thomson, Brayton, Claude, Stirling, Gifford-McMahon, and pulse tube cryocoolers. All of these methods rely on gas compression and expansion. The characteristics as well as the advantage and disadvantages associated with each method are discussed with special emphasis on the applicability of each method for cooling high-T. superconducting devices. Temperatures of about 10 K and below are required for the cooling of low-T, devices, where high-T, devices can operate at temperatures in the range of 60 to 80 K. Cooling for only the latter types of devices are addressed in this chapter. Problems associated with the use of cryocoolers in these applications have been the focus of much research in the last decade. Recent developments and improvements in cryocoolers are discussed and remaining problem areas are listed. Progress toward the development of low-cost cryocoolers for commercial applications of superconductivity is reviewed. Examples are given regarding the use of cryocoolers in cooling superconducting electronic devices.
Crycoolers and High-T<sub>c</sub> Devices
High Temperature Superconductor Symposium Chapter 9 for Handbook of High Temperature Superconductor Electronics,
Crycoolers and High-T<sub>c</sub> Devices, High Temperature Superconductor Symposium Chapter 9 for Handbook of High Temperature Superconductor Electronics,
(Accessed June 3, 2023)