Indexed on: 01 Nov '84Published on: 01 Nov '84Published in: Journal of low temperature physics
We describe the philosophy and practice of a new method of nuclear cooling in which the copper refrigerant is immersed directly in the3He sample to be cooled using a guard cell configuration. The method has been used to cool liquid3He to ∼120 µK. We also describe a variant of the method intended for cooling metallic samples, by which a platinum NMR thermometer has been cooled to ∼13 µK. Finally, in an appendix we suggest a very simple nuclear cooling method utilizing the copper flakes used in the manufacture of paint, which will cool liquid3He to around 1 mK with a minimum of cryogenic effort.