The extended Bean critical state model for superconducting 3-axes ellipsoid and its application for obtaining the bulk critical field Hc1 and the pinning current Jc in high- Tc superconducting single crystals

Abstract

The method of determination of the pinning current density J c and the bulk first critical field H c1 from the magnetization data of high T c superconducting single crystals is presented. The method is based on the original critical state model regarding the shape of the sample, the change of the demagnetization factor with flux penetration, real distribution of the magnetic field and equilibrium flux density within the sample. The method was applied to Tl 2Ba 2CaCu 2O x single crystals.