Vortex dynamics and second magnetization peak in PrFeAsO$_{0.60}$F$_{0.12}$ superconductor

TL;DR

This study investigates vortex behavior in PrFeAsO$_{0.60}$F$_{0.12}$ superconductor, revealing a second magnetization peak, vortex creep crossover, and a vortex phase diagram, highlighting moderate vortex motion and pinning mechanisms.

Contribution

It provides a detailed analysis of vortex dynamics and pinning mechanisms in PrFeAsO$_{0.60}$F$_{0.12}$, including the vortex phase diagram and crossover behavior.

Findings

Second magnetization peak observed.

Vortex creep crossover from elastic to plastic.

Vortex phase diagram constructed.

Abstract

We have studied the vortex dynamics in the PrFeAsO$_{0.60}$F$_{0.12}$ superconducting sample by dc magnetization and dynamic magnetization-relaxation rate $(Q)$ measurements. The field dependence of the superconducting irreversible magnetization $M_s$ reveals a second magnetization peak or fishtail effect. The large value of $Q$ is an indication of moderate vortex motion and relatively weak pinning energy. Data analysis based on the generalized inversion scheme suggests that the vortex dynamics can be described by the collective pinning model. The temperature dependence of the critical current is consistent with the pinning due to the spatial variation in the mean free path near a lattice defect ($\delta l$ pinning). The temperature and field dependence of $Q$ indicates a crossover from elastic to plastic vortex creep with increasing temperature and magnetic field. Finally, we have constructed the vortex phase diagram based on the present data.