Magnetic flux jumps in textured Bi2Sr2CaCu2O(8+d)

TL;DR

This study investigates magnetic flux jumps in textured Bi2Sr2CaCu2O(8+d) using magnetization measurements, revealing how temperature, magnetic field, sample history, and thermal conditions influence flux stability and flux creep phenomena.

Contribution

It provides new insights into the effects of sample history, thermal environment, and demagnetizing factors on flux jumps in high-temperature superconductor Bi2Sr2CaCu2O(8+d).

Findings

Flux jumps occur between 1.95 K and 6 K with magnetic fields up to 9 T.

Sample history and thermal conditions significantly affect flux jumping behavior.

Strong flux creep correlates with flux jumps, influenced by sweep rate and environmental heat exchange.

Abstract

Magnetic flux jumps in textured Bi2Sr2CaCu2O(8+d) have been studied by means of magnetization measurements in the temperature range between 1.95 K and Tc, in an external magnetic field up to 9 T. Flux jumps were found in the temperature range 1.95 K - 6 K, with the external magnetic field parallel to the c axis of the investigated sample. The effect of sample history on magnetic flux jumping was studied and it was found to be well accounted for by the available theoretical models. The magnetic field sweep rate strongly influences the flux jumping and this effect was interpreted in terms of the influence of both flux creep and the thermal environment of the sample. Strong flux creep was found in the temperature and magnetic field range where flux jumps occur suggesting a relationship between the two. The heat exchange conditions between the sample and the experimental environment also influence the flux jumping behavior. Both these effects stabilize the sample against flux instabilities, and this stabilizing effect increases with decreasing magnetic field sweep rate. Demagnetizing effects are also shown to have a significant influence on flux jumping.