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arXiv · 2310.12573

Coupling of strain and magnetism in manganite-based complex oxide heterostructures

Abstract

Complex oxide thin films and heterostructures offer a wide range of properties originating from the intrinsic coupling between lattice strain and magnetic/electronic ordering. This article reviews experimental, phenomenological, and theoretical analyses of the coupling of strain with electronic and magnetic properties of mixed valence manganite heterostructures. The influence of epitaxial strain on the magnetic properties of manganite films is measured using macroscopic magnetization measurements and shown mixed reports suggesting, both, an increase and decrease in ferromagnetic phases on the application of the strain. Using polarized neutron reflectivity (PNR), a simultaneous measurement of transport and magnetic properties of manganite thin films showed direct evidence of modification in the magnetic properties on the application of bending strain. The coupling coefficient of strain and magnetism of manganite heterostructures was estimated using PNR, which not only helped to understand the correlation of elastic strain with magnetism but also explained the condition of magnetic phase order change in the phase-separated systems within a phenomenological Ginzburg Landau theory. An overview is also provided of the current perspectives and existing studies on the influence of strain on structure, electronic, magnetic, magnetic anisotropy, phase coexistence and magnetocaloric properties of mixed valence manganite heterostructures. Based on the understanding of a diverse range of perovskite functionalities, detailed perspectives on how the coupling of strain and magnetism open up pathways toward the emergence of novel device design features including the different ways of applying uniform strain, are discussed.

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Surendra Singh. 2023-10-19. Coupling of strain and magnetism in manganite-based complex oxide heterostructures. https://arxiv.org/abs/2310.12573

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