Anomalous Pressure Dependence of the Superconducting Transition Temperature in TlNi$_2$Se$_{2-x}$S$_x$

S. K. Goh; H. C. Chang; P. Reiss; P. L. Alireza; Y. W. Cheung; S. Y. Lau; Hangdong Wang; Qianhui Mao; Jinhu Yang; Minghu Fang; F. M. Grosche; M. L. Sutherland

doi:10.1103/physrevb.90.201105

arXiv · 1410.2506

Anomalous Pressure Dependence of the Superconducting Transition Temperature in TlNi$_2$Se$_{2-x}$S$_x$

S. K. Goh·H. C. Chang·P. Reiss·P. L. Alireza·Y. W. Cheung·S. Y. Lau·Hangdong Wang·Qianhui Mao·Jinhu Yang·Minghu Fang·F. M. Grosche·M. L. Sutherland

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Abstract

We report the pressure dependence of the superconducting transition temperature, $T_c$, in TlNi$_2$Se$_{2-x}$S$_x$ detected via the AC susceptibility method. The pressure-temperature phase diagram constructed for TlNi$_{2}$Se$_{2}$, TlNi$_{2}$S$_{2}$ and TlNi$_{2}$SeS exhibits two unexpected features: (a) a sudden collapse of the superconducting state at moderate pressure for all three compositions and (b) a dome-shaped pressure dependence of $T_c$ for TlNi$_{2}$SeS. These results point to the nontrivial role of S substitution and its subtle interplay with applied pressure, as well as novel superconducting properties of the TlNi$_2$Se$_{2-x}$S$_x$ system.

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S. K. Goh, H. C. Chang, P. Reiss, P. L. Alireza, Y. W. Cheung, S. Y. Lau, Hangdong Wang, Qianhui Mao, Jinhu Yang, Minghu Fang, F. M. Grosche, M. L. Sutherland. 2014-10-09. Anomalous Pressure Dependence of the Superconducting Transition Temperature in TlNi$_2$Se$_{2-x}$S$_x$. https://doi.org/10.1103/physrevb.90.201105

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