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arXiv · 1309.3454

Enhancement of the Superconducting Transition Temperature in FeSe Epitaxial Thin Films by Anisotropic Compression

Fuyuki Nabeshima·Yoshinori Imai·Masafumi Hanawa·Ichiro Tsukada·Atsutaka Maeda
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Abstract

In order to investigate the effects of in-plane strain on the superconductivity of FeSe, epitaxial thin films of FeSe were fabricated on CaF$_2$ substrates. The films are compressed along the a-axis and their superconducting transition temperatures $T_{\mathrm c}^{\mathrm {zero}}$ reach 11.4 K, which is approximately 1.5 times higher than that of bulk crystals. The $T_{\mathrm c}$ values are weakly dependent on the ratio of the lattice constants, $c$ / $a$, compared to that of Fe(Se,Te). Our results indicate that even a binary system FeSe has room for improvement, and will open a new route for the application of Fe-based superconductors.

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Fuyuki Nabeshima, Yoshinori Imai, Masafumi Hanawa, Ichiro Tsukada, Atsutaka Maeda. 2013-09-13. Enhancement of the Superconducting Transition Temperature in FeSe Epitaxial Thin Films by Anisotropic Compression. https://doi.org/10.1063/1.4826945

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