MAGNETOCALORIC EFFECT IN FERROMAGNETIC AND SUPERCONDUCTING MATERIALS

Computer studies are made illustrating the similarities of the interes ting change of sign in the magnetocaloric effect between the vortex la ttice in superconductors and a system of interacting magnons and phono ns in ferromagnetic materials. This change happens in the superconduct ing system when the external magnetic field approaches a critical valu e, while the critical point in the ferromagnetic system is where the e xternal magnetic field turns the direction of magnetization from the e asy to the hard direction. The usefulness for the study of high-temper ature superconductors is suggested.