Low-frequency AC susceptibility due to the interplay of loss mechanisms inHTS

The analysis of low-frequency sc susceptibility is complicated because the hysteretic losses due to pinning and the eddy-current tosses are not simply additive, We show that the electromagnetic response of both ideal and noni deal type-II superconductors can be well described with a common nonlinear response function. This function makes a consistent description of the cros sover from the power-law E(J) of pur-creep to the ohmic flux-flow regime. W e interpret the scaling behavior of sc susceptibility with this nonlinear e quation.