Charge order in photosensitive Bi0.4Ca0.6MnO3 films

TL;DR

This study investigates the charge order phase in Bi0.4Ca0.6MnO3 films, revealing strain-dependent resonant x-ray scattering and photoinduced resistivity changes near room temperature, advancing understanding of their photosensitivity.

Contribution

It provides the first detailed structural and electronic characterization of charge order in these films, highlighting strain effects on their resonant scattering and photosensitive properties.

Findings

Lattice distortions linked to charge order are observed in all films.

Resonant x-ray scattering varies with strain, indicating different mechanisms.

Photoinduced resistivity changes occur near room temperature.

Abstract

We report structural and electronic characterization of the charge order phase in Bi0.4Ca0.6MnO3 films, in which photoinduced resistivity changes have been observed at temperatures approaching room temperature. In all films, lattice distortions associated with the charge order are observed, and both the wavevectors and displacements of the distortions are in the plane of the film. Films under compressive and tensile strain are observed to have different resonant x-ray scattering characteristics-- a result that may shed light on the mechanism responsible for the photosensitivity exhibited by this material.