Effect of strain on the electrical transport and magnetization of the epitaxial Pr0.5Ca0.5MnO3/La0.5Ca0.5MnO3/ Pr0.5Ca0.5MnO3 trilayer structures

TL;DR

This study investigates how strain influences electrical transport and magnetization in epitaxial Pr0.5Ca0.5MnO3/La0.5Ca0.5MnO3/Pr0.5Ca0.5MnO3 trilayer structures, revealing strain-dependent magnetic and electronic behaviors on different substrates.

Contribution

It demonstrates how substrate-induced strain affects magnetic ordering and transport properties in complex oxide trilayers, highlighting interfacial effects and Jahn-Teller distortions.

Findings

On LAO, samples show thermally activated transport behavior.

On STO, increasing LCMO thickness induces metal-like transport.

Magnetic properties are influenced by interfacial effects and strain.

Abstract

Epitaxial trilayer structures consisting of two antifferomagnetic charge/orbital order insulators Pr0.5Ca0.5MnO3 (PCMO) and La0.5Ca0.5MnO3 (LCMO) are grown on (001)-oriented SrTiO3 and LaAlO3 substrates. In this trilayer series, a thin film of LCMO with various thicknesses is sandwiched between the two fixed thicknesses of PCMO. These samples show a Curie temperature with a hysteretic field dependent magnetization at 10 K, although the individual compounds are antiferromagnetic. The zero field electronic transport of all samples on LAO shows thermally activated behavior, while the thermally activated behavior is suppressed and a metal-like transport is appearing for the samples on STO as the LCMO layer thickness increases above 10 unit cell. We have discussed these magnetic and transport properties of the trilayer structures on STO and LAO by the interfacial effect due to the stabilized CO state and the vibration mode of Jahn-Teller distortion.