パルス磁場を用いたBi系酸化物超伝導体における磁束の粘性力の測定

抄録

The viscous force acting on the magnetic flux in a high-T_c Bi₂Sr₂Ca₂Cu₃O₁₀ superconductor was evaluated by applying a pulsed magnetic field. It was found that the magnetic flux intruding into the superconductor moves at a speed of about 50 m/s. The viscous force and the pinning force in a Bi-based high-T_c superconductor are discussed in the framework of the critical state model. The viscosity (η/φ₀) of the magnetic flux was estimated to be about 1×10⁵A·s/m³.