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arXiv · 1611.01128

Room temperature multiferroism in polycrystalline thin films of gallium ferrite

Monali Mishra·Amritendu Roy·Ashish Garg·Rajeev Gupta·Somdutta Mukherjee
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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.

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Monali Mishra, Amritendu Roy, Ashish Garg, Rajeev Gupta, Somdutta Mukherjee. 2016-11-03. Room temperature multiferroism in polycrystalline thin films of gallium ferrite. https://arxiv.org/abs/1611.01128

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