Nematic properties of FeSe$_{1-x}$Te$_{x}$ crystals with a low Te content

Y. A. Ovchenkov; D. A. Chareev; V. A. Kulbachinskii; V. G. Kytin; D. E. Presnov; Y. Skourski; L. V. Shvanskaya; O. S. Volkova; D. V. Efremov; A. N. Vasiliev

arXiv · 1909.00711

Nematic properties of FeSe$_{1-x}$Te$_{x}$ crystals with a low Te content

Y. A. Ovchenkov·D. A. Chareev·V. A. Kulbachinskii·V. G. Kytin·D. E. Presnov·Y. Skourski·L. V. Shvanskaya·O. S. Volkova·D. V. Efremov·A. N. Vasiliev

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Abstract

We report on the synthesis and physical properties of FeSe$_{1-x}$Te$_x$ single crystals with a low Te content (x = 0.17, 0.21, 0.25), where the replacement of Se with Te partially suppresses superconductivity. Resistivity and Hall effect measurements indicate weak anomalies at elevated temperatures ascribed to nematic transitions. A quasi-classical analysis of transport data, including in a pulsed magnetic field of up to 25 T, confirms the inversion of majority carriers type from holes in FeSe to electrons in FeSe$_{1-x}$Te$_x$ at x $>$ 0.17. The temperature-dependent term in the elastoresistance of the studied compositions has a negative sign, which means that for substituted FeSe compositions, the elastoresistance is positive for hole-doped materials and negative for electron-doped materials just like in semiconductors such as silicon and germanium.

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Y. A. Ovchenkov, D. A. Chareev, V. A. Kulbachinskii, V. G. Kytin, D. E. Presnov, Y. Skourski, L. V. Shvanskaya, O. S. Volkova, D. V. Efremov, A. N. Vasiliev. 2019-09-02. Nematic properties of FeSe$_{1-x}$Te$_{x}$ crystals with a low Te content. https://arxiv.org/abs/1909.00711

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