Characteristics of Holes Investigated by ESR in High-T_cphase of Bi(Pb)-Sr-Ca-Cu-O System

Abstract

Measurements of nonresonant and ESR absorption are made in the high- T c phase of the Bi(Pb)-Sr-Ca-Cu-O system. Two components of ESR signals have been detected above the superconducting transition temperature T c . One is anisotropic and the other is isotropic. The isotropic spectrum is not considered to arise from impurities. The nonresonant microwave absorption near zero magnetic field is greatly enhanced at T c and the ESR signals are almost completely masked. The origin of the ESR is discussed in relation to doped holes.