magnetic refrigerator [mag`ned·ik ri`frij·ǝ´rād·ǝr] CRYOGENICS A device for keeping substances cooled to about 0.2 K, in which a working substance consisting of a paramagnetic salt undergoes a cycle of processes which approximates a Carnot cycle between a high- temperature reservoir consisting of a liquid-helium bath at 1.2 K and a low- temperature reservoir consisting of the substance to be cooled, and isentropic cooling of the working substance is accomplished by demagnetization. |