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arXiv · 1712.03749

Conventional Superconductivity in Type II Dirac Semimetal PdTe$_2$

Shekhar Das·Amit·Anshu Sirohi·Lalit Yadav·Sirshendu Gayen·Yogesh Singh·Goutam Sheet
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Abstract

The transition metal dichalcogenide PdTe$_2$ was recently shown to be a unique system where a type II Dirac semimetallic phase and a superconducting phase co-exist. This observation has led to wide speculation on the possibility of the emergence of an unconventional topological superconducting phase in PdTe$_2$. Here, through direct measurement of the superconducting energy gap by scanning tunneling spectroscopy (STS), and temperature and magnetic field evolution of the same, we show that the superconducting phase in PdTe$_2$ is conventional in nature. The superconducting energy gap is measured to be 326 $μ$eV at 0.38 K and it follows a temperature dependence that is well described within the framework of Bardeen-Cooper-Schriefer's (BCS) theory of conventional superconductivity. This is surprising because our quantum oscillation measurements confirm that at least one of the bands participating in transport has topologically non-trivial character.

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Shekhar Das, Amit, Anshu Sirohi, Lalit Yadav, Sirshendu Gayen, Yogesh Singh, Goutam Sheet. 2018-01-12. Conventional Superconductivity in Type II Dirac Semimetal PdTe$_2$. https://doi.org/10.1103/physrevb.97.014523

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