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arXiv · 1801.03853

Strain induced changes of electronic properties of B-site ordered double perovskite Sr$_2$CoIrO$_6$ thin films

S. Esser·C. F. Chang·C. -Y. Kuo·S. Merten·V. Roddatis·T. D. Ha·A. Jesche·V. Moshnyaga·H. -J. Lin·A. Tanaka·C. T. Chen·L. H. Tjeng·P. Gegenwart
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Abstract

B-site ordered thin films of double perovskite Sr$_2$CoIrO$_6$ were epitaxially grown by a metal-organic aerosol deposition technique on various substrates, actuating different strain states. X-ray diffraction, transmission electron microscopy and polarized far-field Raman spectroscopy confirm the strained epitaxial growth on all used substrates. Polarization dependent Co $L_{2,3}$ X-ray absorption spectroscopy reveals a change of the magnetic easy axis of the antiferromagnetically ordered (high-spin) Co$^{3+}$ sublattice within the strain series. By reversing the applied strain direction from tensile to compressive, the easy axis changes abruptly from in-plane to out-of-plane orientation. The low-temperature magnetoresistance changes its sign respectively and is described by a combination of weak anti-localization and anisotropic magnetoresistance effects.

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S. Esser, C. F. Chang, C. -Y. Kuo, S. Merten, V. Roddatis, T. D. Ha, A. Jesche, V. Moshnyaga, H. -J. Lin, A. Tanaka, C. T. Chen, L. H. Tjeng, P. Gegenwart. 2018-01-11. Strain induced changes of electronic properties of B-site ordered double perovskite Sr$_2$CoIrO$_6$ thin films. https://doi.org/10.1103/physrevb.97.205121

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