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arXiv · 1708.05973

An increase in $T_c$ under hydrostatic pressure in the superconducting doped topological insulator Nb$_{0.25}$Bi$_2$Se$_3$

M. P. Smylie·K. Willa·K. Ryan·H. Claus·W. -K. Kwok·Y. Qiu·Y. S. Hor·U. Welp
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Abstract

We report an unexpected positive hydrostatic pressure derivative of the superconducting transition temperature in the doped topological insulator \NBS via $dc$ SQUID magnetometry in pressures up to 0.6 GPa. This result is contrary to reports on the homologues \CBS and \SBS where smooth suppression of $T_c$ is observed. Our results are consistent with recent Ginzburg-Landau theory predictions of a pressure-induced enhancement of $T_c$ in the nematic multicomponent $E_u$ state proposed to explain observations of rotational symmetry breaking in doped Bi$_2$Se$_3$ superconductors.

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M. P. Smylie, K. Willa, K. Ryan, H. Claus, W. -K. Kwok, Y. Qiu, Y. S. Hor, U. Welp. 2017-08-20. An increase in $T_c$ under hydrostatic pressure in the superconducting doped topological insulator Nb$_{0.25}$Bi$_2$Se$_3$. https://doi.org/10.1016/j.physc.2017.10.010

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