Asymmetric Ground States in La$_{0.67}$Sr$_{0.33}$MnO$_3$/BaTiO$_3$ heterostructures Induced by Flexoelectric Bending

TL;DR

This study demonstrates that uniaxial strain via bending can continuously tune the magnetotransport properties of La$_{0.67}$Sr$_{0.33}$MnO$_3$ films, inducing asymmetric magnetic states through flexoelectric effects, with implications for flexible electronics.

Contribution

It reveals how flexoelectric fields and Jahn-Teller distortions under uniaxial strain induce asymmetric ground states in LSMO/BaTiO$_3$ heterostructures, a novel multi-field regulation approach.

Findings

Electrical conductivity and Curie temperature are enhanced by bending.

Resistivity decay rate differs between u-shape and n-shape bending.

Asymmetric magnetic states are caused by flexoelectric effects and Jahn-Teller distortion.

Abstract

Misfit strain delivered from single-crystal substrates typically modifies the ground states of transition metal oxides, generating increasing interests in designing modern transducers and sensors. Here, we demonstrate that magnetotransport properties of La$_{0.67}$Sr$_{0.33}$MnO$_3$ (LSMO) films were continuously tuned by uniaxial strain produced by a home-designed bending jig. The electrical conductivity and Curie temperature of LSMO films are enhanced by bending stresses. The resistivity of a u-shape bended LSMO decays three times faster than that of a n-shape bended LSMO as a response to the same magnitude of strain. The asymmetric magnetic states in uniaxially strained LSMO are attributed to the dual actions of Jahn-Teller distortion and strain gradient mediated flexoelectric fields in an adjacent ferroelectric layer. These findings of multi-field regulation in a single material provide a feasible means for developing flexible electronic and spintronic devices.