Combined use of superconducting magnets and suitable paramagnetic or ferromagnetic materials makes possible the utilization of the magnetocaloric effect to efficient refrigeration cycles starting as high as room temperature. The present article describes the fundamental principles of three basic magnetic refrigeration cycles corresponding to the reversed Carnot, Stirling and Ericsson cycle in gas refrigeration. A brief review of the present status of research and possible applications of magnetic refrigerators are made.
