Critical current density from magnetization hysteresis data using the critical-state model

We present an exact method to extract the critical current density (J(c).) from the irreversible magnetization data (M-H) using the Bean's critical-state model. The weakly pinned superconducting samples are known to display an anomalous peak in J(c) with the increase in H, which is referred to as the peak effect phenomenon and it is in contemporary focus. We show that the shape of the hysteresis bubble identifying peak effect in J(c)(H) in the M-H data is asymmetric.