Room temperature multiferroism in polycrystalline thin films of gallium ferrite

TL;DR

This study demonstrates room temperature multiferroic behavior in polycrystalline gallium ferrite thin films, showing potential for integration into multifunctional devices.

Contribution

First comprehensive characterization of room temperature multiferroism in polycrystalline GFO thin films on common substrates.

Findings

Confirmed single-phase GFO with nano-sized crystallites.

Observed ferri to paramagnetic transition at ~300 K.

Detected high coercive field ferroelectric switching at room temperature.

Abstract

Sol-gel deposited (010) textured polycrystalline thin films of gallium ferrite (GaFeO3 or GFO) on n-Si(100) and Pt/Si(111) substrates are characterized for room temperature multiferroism. Structural characterization using X-ray diffraction and Raman spectroscopy confirms formation of single phase with nano-sized crystallites. Temperature dependent magnetization study demonstrates ferri to paramagnetic transition at ~300 K. Room temperature piezoresponse force microscopic analysis reveals local 180 degree phase switching of ferroelectric domains at very high coercive field EC, ~ 1350 kV/cm consistent with recent experimental and first-principles studies. Our study opens up possibility of integrating polycrystalline GFO in novel room temperature multiferroic devices.