Practical Cryostat Design and Construction

Dr. Zuyu Zhao received his B.S. degree from Fudan University in 1982, Class 77. He came to the United States in 1983 with the World Bank Scholarship program and graduated from Northwestern University with a Ph.D. degree in physics in 1990. He then spent two and a half years working at Harvard University as a Research Associate and set up a new ultra-low temperature lab pursuing Bose-Einstein condensation on spin polarized hydrogen. Dr. Zhao joined Janis Research Company (later American Cryogenics dba JanisULT) in 1993 and focused on developing custom ultra-low temperature facilities for the research and science community. He was a scientist at both Janis Research and JanisULT as well as the trustee of the company. Dr. Zhao also served from July 1, 2007 through June 30, 2013 as an elected member of the American Institute of Physics (Physics Today) Advisory Committee. Before he retired in late 2023, he had served as the Chief Cryogenic Scientist for 15 months after the business merged to FormFactor LLC and helped with smooth business and technical transfer.Dr. Zhitao Wang received his B.S. degree from Hebei University in 2001. He then pursued his Ph.D. at the Institute of Physics, Chinese Academy of Sciences, during which he spent two years at Tohoku University as an exchange student. After receiving his Ph.D. in 2006, Dr. Wang worked at Trinity College Dublin, Pacific Northwest National Laboratory, and Tufts University (joint with Harvard University). His research focused on surface science at cryogenic temperatures, particularly low-temperature scanning probe microscopy. In 2017, he joined Janis Research Company (later JanisULT) as a cryogenic engineer, specializing in custom low-temperature systems. After FormFactor acquired JanisULT in 2022, he became a cryogenic scientist, working on the development of customized helium-3 systems and dilution refrigerators. In late 2024, Dr. Wang joined Commonwealth Fusion Systems, where he is currently helping to develop cooling systems for powerful high-Tc superconducting magnets.

• Chapter 1: He-3 Cryostat - Basic Concept, Design and Construction.Chapter 2: Sample Loading and Sample Holders in Customized Cryostats.Chapter 3: Cryostat Design for High-Field Magnet with Room Temperature Bore.Chapter 4: Salt Pill Growth for the Adiabatic Demagnetization Refrigerators.Chapter 5: Joule-Thomson Condensing Assembly Unit.Chapter 6: Excessive Cooling Power from Pulse Tube Refrigerators.Chapter 7: Special Cryostats.Chapter 8: Thermal Boundary Conductance: Modelling and Examples.Chapter 9: Thermometers at Cryogenic Temperatures.Chapter 10: Impact of High Magnetic Fields on Millikelvin Temperatures.Chapter 11: Sample Probe for High-Voltage Operations at 400 mK.Chapter 12: Ultra-High Vacuum Technologies.Chapter 13: Vapor-Cooled Current Leads for High Field Magnets.Chapter 14: Copper Thermal Link Fabrication.Chapter 15: Multilayer Superinsulation.Chapter 16: Vibration Reduction.Chapter 17: Cryogenic Electrical Wiring and Cabling and Vacuum Feedthroughs.Chapter 18: Diverse Techniques in Cryogenic Engineering.Appendix. Index.