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arXiv · 1811.02634

Improved Single-Crystal Growth of Sr$_2$RuO$_4$

J. S. Bobowski·N. Kikugawa·T. Miyoshi·H. Suwa·S. Yonezawa·D. A. Sokolov·A. P. Mackenzie·Y. Maeno
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Abstract

High-quality single crystals are essentially needed for the investigation of the novel bulk properties of unconventional superconductors. The availability of such crystals grown by the floating-zone method has helped to unveil the unconventional superconductivity of the layered perovskite Sr$_2$RuO$_4$, which is considered as a strong candidate of a topological spin-triplet superconductor. Yet, recent progress of investigations urges further efforts to obtain ultimately high-quality crystalline samples. In this paper, we focus on the method of preparation of feed rods for the floating-zone melting and report on the improvements of the crystal growth. We present details of the improved methods used to obtain crystals with superconducting transition temperatures $T_\mathrm{c}$ that are consistently as high as 1.4 K, as well as the properties of these crystals.

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J. S. Bobowski, N. Kikugawa, T. Miyoshi, H. Suwa, S. Yonezawa, D. A. Sokolov, A. P. Mackenzie, Y. Maeno. 2018-11-05. Improved Single-Crystal Growth of Sr$_2$RuO$_4$. https://doi.org/10.3390/condmat4010006

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