Equilibrium tuned by a magnetic field in phase separated manganite

TL;DR

This study investigates how magnetic fields influence the equilibrium phase composition in a phase-separated manganite, revealing dynamic relaxation behaviors and a method to determine the equilibrium state through magnetic and resistive measurements.

Contribution

It introduces a novel experimental procedure to determine the equilibrium phase fraction in a phase-separated manganite system using magnetic relaxation derivatives.

Findings

Dynamic phase relaxation observed between 60-120K.

A new method to determine equilibrium phase fraction.

Correlation between relaxation behavior and proximity to equilibrium.

Abstract

We present magnetic and transport measurements on La5/8-yPryCa3/8MnO3 with y = 0.3, a manganite compound exhibiting intrinsic multiphase coexistence of sub-micrometric ferromagnetic and antiferromagnetic charge ordered regions. Time relaxation effects between 60 and 120K, and the obtained magnetic and resistive viscosities, unveils the dynamic nature of the phase separated state. An experimental procedure based on the derivative of the time relaxation after the application and removal of a magnetic field enables the determination of the otherwise unreachable equilibrium state of the phase separated system. With this procedure the equilibrium phase fraction for zero field as a function of temperature is obtained. The presented results allow a correlation between the distance of the system to the equilibrium state and its relaxation behavior.