Title

Irreversible heat flow across phase boundaries in phase-separated manganites

Publication Date

9-5-2020

Document Type

Article

Publication Title

Journal of Alloys and Compounds

Volume

834

DOI

10.1016/j.jallcom.2020.155129

Abstract

We have investigated the change in entropy with direct measurements of heat flow as a function of magnetic field at fixed temperatures across the entire phase diagram of the phase-separated (PS) compound La0.25Pr0.375Ca0.375MnO3 (LPCMO). At this composition, the compound shows competing charge-ordered/antiferromagnetic (CO/AF) ground states. Under a fixed temperature, we observed an increase in hysteresis in the entropy as a function of the applied field. The heat flux shows progressively irreversible hysteresis, which characterizes the energy barriers between the two competing ground states, as the temperature is lowered. The increase in the heat loss correlates with the increase in magnetic viscosity in the phase-separated state.

Funding Number

DE-NA0003525

Funding Sponsor

U.S. Department of Energy

Keywords

Avalanche effect, DSC, Entropy, Heat flow, Manganites, Phase transition

Department

Physics and Astronomy

COinS