Effect of strain on phase separation and de-vitrification of magnetic glass state in thin films of La5/8-yPryCa3/8MnO3 (y=0.45)

TL;DR

This study investigates how substrate-induced strain affects phase separation and magnetic glass behavior in thin films of La5/8-yPryCa3/8MnO3, revealing strain-dependent melting of insulating phases and evidence of devitrification of a magnetic glass-like state.

Contribution

It demonstrates the influence of substrate strain on phase behavior and glass-like states in La5/8-yPryCa3/8MnO3 thin films, highlighting the persistence of phase separation despite strain variations.

Findings

Strain affects the melting of insulating phases in thin films.

Magnetic glass-like states exhibit devitrification under magnetic field.

All films show phase separation and metastable glass-like behavior.

Abstract

We present our study of effect of substrate induced strain on the La5/8-yPryCa3/8MnO3 (y=0.45), thin films grown on LaAlO3, NdGaO3 and SrTiO3 susbtrates that show large scale phase separation. It is observed that unstrained films grown on NdGaO3 behave quite similar to bulk material but the strained film grown on SrTiO3 show melting of insulating phase to metallic phase at low temperatures. However, the large scale phase separation and metastable glass-like state is observed in all the films despite difference in substrate induced strain. The measurements of resistivity as a function of temperature under cooling and heating in unequal field (CHUF) protocol elucidates the presence of glass-like meta-stable phase generated due to kinetic arrest of first order transformation in all the films. Like structural glasses, these magnetic glass-like phase shows evidence of devitrification of the arrested charge order-antiferromagnetic insulator (CO-AFI) phase to equilibrium ferromagnetic metallic (FMM) phase with isothermal increase of magnetic field and/or iso-field warming. These measurements also clearly brought out the equilibrium ground state of this system to be FMM and metastable glass-like phase to be AFI phase.