Magnetic non-uniformity and thermal hysteresis of magnetism in a manganite thin film

TL;DR

This study investigates the magnetic and chemical depth profiles of a manganite thin film, revealing phase coexistence and a first-order ferromagnetic transition with thermal hysteresis.

Contribution

It provides detailed depth-resolved magnetic and chemical profiles of a manganite film, highlighting phase coexistence and transition characteristics.

Findings

Magnetic phases coexist as a function of depth.

Chemical composition varies with depth.

Ferromagnetic order shows thermal hysteresis indicating a first-order transition.

Abstract

We measured the chemical and magnetic depth profiles of a single crystalline (La$_{1-x}$Pr$_x$)$_{1-y}$Ca$_y$MnO$_{3-{\delta}}$ (x = 0.52\pm0.05, y = 0.23\pm0.04, {\delta} = 0.14\pm0.10) film grown on a NdGaO3 substrate using x-ray reflectometry, electron microscopy, electron energy-loss spectroscopy and polarized neutron reflectometry. Our data indicate that the film exhibits coexistence of different magnetic phases as a function of depth. The magnetic depth profile is correlated with a variation of chemical composition with depth. The thermal hysteresis of ferromagnetic order in the film suggests a first order ferromagnetic transition at low temperatures.