Electric field control of photoinduced effect in La$_{0.7}$Sr$_{0.3}$MnO$_3$/LaTiO$_3$/SrTiO$_3$ heterostructure

TL;DR

This study demonstrates how light and electric fields can be combined to control resistance states in a La0.7Sr0.3MnO3 heterostructure, revealing mechanisms involving interfacial charge and orbital manipulation.

Contribution

It introduces a method to tune resistance in manganite heterostructures using combined light and electric fields, with insights into interfacial charge and orbital effects.

Findings

Resistance change of about +/-7.5% with light and electric field

Interfacial LaTiO3 layer influences photoinduced effects

Photoexcited electrons and charge injection modulate orbital occupancy

Abstract

In this work we have studied the effect of light and electric field on the electrical properties of La0.7Sr0.3MnO3 (LSMO) film at 300 K. Taking advantage of it's charge, spin, orbital and lattice degrees of freedom, we have successfully shown that light and electric field together can be used to tune the resistance states of the manganite system. Using applied gate voltage (Vg) and light we were able to obtain a change in resistance of about +/-7.5%. Furthermore, incorporating an ultra thin interfacial LaTiO3 (LTO) layer provides valuable insight on the origin of the photoinduced effect. The observed photoinduced effect is attributed to photoexcited down spin eg electrons, interfacial charge injection and manipulation of orbital occupancy depending on the gate voltage and wavelength of light.