2021/08/18 by Joshi, T., Belanger, D. P., Tan, Y. T. +2
#FOS: Physical sciences #J.2 #Materials Science (cond-mat.mtrl-sci)
paper · doi:10.48550/arxiv.2108.07965
The different magnetic behaviors of LaCoO3 films grown on LaAlO3 and SrTiO3 are related to the Co-O-Co bond angles and the constraints imposed on the Co-O bond lengths by the substrate geometries. Long-range magnetic order occurs below T ~ 90 K when the Co-O-Co bond angle is greater than 163 degrees, consistent with the behavior of bulk and nanoparticles forms of LaCoO3. A LaAlO3 substrate prevents magnetic long-range order at low temperatures near the film-substrate interface and collinear antiferromagnetic sublattices away from the interface. At low temperatures, the antiferromagnetically ordered sublattices are non-collinear in films grown on SrTiO3 substrates, leading to a significant net moment.