Comment on ``Plateaus Observed in the Field profile of Thermal Conductivity in the Superconductor Bi_2Sr_2CaCu_2O_8''

TL;DR

This paper investigates the magnetic field dependence of thermal conductivity in Bi_2Sr_2CaCu_2O_8, challenging previous interpretations by showing background thermal conductivity varies with field profile, indicating different underlying mechanisms.

Contribution

The study provides new experimental evidence that the thermal conductivity background depends on magnetic field history, contradicting prior explanations of field-independent behavior.

Findings

Thermal conductivity above a threshold field is field-independent.

Background thermal conductivity varies with magnetic field profile.

Results challenge previous interpretations of thermal conductivity behavior.

Abstract

We studied the thermal conductivity of a Bi_2Sr_2CaCu_2O_8 single crystal as a function of a magnetic field ramped up and down and then reversed. As recently discovered by Krishana et al., we observed a field-independent thermal conductivity above a threshold field. However, our measurements show that the magnitude of background thermal conductivity depends on the field profile in the sample. This is incompatible with the interpretation put forward by Krishana and co-workers.