1969 Volume 4 Issue 1 Pages 26-34
Several methods of refrigeration are available to attain the temperature below one degree Kelvin. These methods utilize adiabatic demagnetization of paramagnetic salts, adiabatic magnetization of superconductors, a Helium three refrigerator and a Helium three-Helium four mixing or dilution refrigerator. The principles and the combination of these refrigeration methods are discussed.
Other methods such as the refrigeration using mechano-caloric effect of Helium II, a Helium three expansion engine which produces cold due to the work done against the osmotic pressure and an adiabatic compression method of Helium three are also reviewed.