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arXiv · 1708.07529

Tensile-Strain Dependent Spin States in Epitaxial LaCoO$_3$ Thin Films

Y. Yokoyama·Y. Yamasaki·M. Taguchi·Y. Hirata·K. Takubo·J. Miyawaki·Y. Harada·D. Asakura·J. Fujioka·M. Nakamura·H. Daimon·M. Kawasaki·Y. Tokura·H. Wadati
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Abstract

The spin states of Co$^{3+}$ ions in perovskite-type LaCoO$_3$, governed by complex interplay between the electron-lattice interactions and the strong electron correlations, still remain controversial due to the lack of experimental techniques which can detect directly. In this letter, we revealed the tensile-strain dependence of spin states, $i. e.$ the ratio of the high- and low-spin states, in epitaxial thin films and a bulk crystal of LaCoO$_3$ via resonant inelastic soft x-ray scattering. The tensile-strain as small as 1.0% was found to realize different spin states from that in the bulk.

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Y. Yokoyama, Y. Yamasaki, M. Taguchi, Y. Hirata, K. Takubo, J. Miyawaki, Y. Harada, D. Asakura, J. Fujioka, M. Nakamura, H. Daimon, M. Kawasaki, Y. Tokura, H. Wadati. 2017-08-24. Tensile-Strain Dependent Spin States in Epitaxial LaCoO$_3$ Thin Films. https://doi.org/10.1103/physrevlett.120.206402

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