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arXiv · 1104.0477

Epitaxial growth of FeSe$_{0.5}$Te$_{0.5}$ thin films on CaF$_2$ substrates with high critical current density

I. Tsukada·M. Hanawa·T. Akiike·F. Nabeshima·Y. Imai·A. Ichinose·S. Komiya·T. Hikage·T. Kawaguchi·H. Ikuta·A. Maeda
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Abstract

In-situ epitaxial growth of FeSe$_{0.5}$Te$_{0.5}$ thin films is demonstrated on a non-oxide substrate CaF$_2$. Structural analysis reveals that compressive stress is moderately added to 36-nm thick FeSe$_{0.5}$Te$_{0.5}$, which pushes up the critical temperature above 15 K, showing higher values than that of bulk crystals. Critical current density at $T$ = 4.5 K reaches 5.9 x 10$^4$ Acm$^{-2}$ at $μ_0H$ = 10 T, and 4.2 x 10$^4$ Acm$^{-2}$ at $μ_0H$ = 14 T. These results indicate that fluoride substrates have high potential for the growth of iron-based superconductors in comparison with popular oxide substrates.

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I. Tsukada, M. Hanawa, T. Akiike, F. Nabeshima, Y. Imai, A. Ichinose, S. Komiya, T. Hikage, T. Kawaguchi, H. Ikuta, A. Maeda. 2011-05-02. Epitaxial growth of FeSe$_{0.5}$Te$_{0.5}$ thin films on CaF$_2$ substrates with high critical current density. https://doi.org/10.1143/apex.4.053101

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