Magnetic-field-modulated microwave-absorption detection in a Bi-Sr-Ca-Cu-O superconductor

Superconducting transitions are observed at 110 K, 100 K, and 72 K in a nominally BiSrCaCu2O x ceramic using the novel technique of magnetic-field-modulated microwave-absorption detection. The response of the BiSrCaCu2O x ceramic to an external magnetic field differs markedly from that of YBa2Cu3O and, in particular, -dT c /dH is much greater in the bismuth sample.