抄録
The current lead is a key component in a superconducting magnet system. Yet heat conduction and ohmic heating of the current lead should be kept to a minimum for economic reasons and for the cryogenic stability of the system. High temperature superconducting materials (HTS) has recently been used to solve the contradiction in the current lead. A third generation current lead, called the Peltier current lead, is described. The Peltier current elementis a heat pump made of N-type and P-type semiconductors. The technology of the Peltier element can be applied with HTS current lead. Experiments with the Peltier current lead demonstrate the reduction of heat leak of 15 to 25%. Since the HTS and the semiconductor are made from Bi-based materials, for exapmle, Bi-2223 for HTS and BiTe (Sb) for the semiconductor, we might made a whole current lead from Bi-based material, and this is one of the functionally gradient material (FGM).
