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arXiv · 1910.13773

Coexistence of type-I and type-II superconductivity in topological superconductor PdTe$_2$

D. Singh·Pabitra K. Biswas·Sungwon Yoon·C. H. Lee·A. D. Hillier·R. P. Singh·Amit Y. Singh·K. -Y. Choi
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Abstract

The type-II Dirac semimetal PdTe2 was recently reported to be a type-I superconductor with a superconducting transition temperature Tc = 1.65 K. However, the recent results from tunneling and point contact spectroscopy suggested the unusual state of a mixture of type-I and type-II superconductivity. These contradictory results mean that there is no clear picture of the superconducting phase diagram and warrants a detailed investigation of the superconducting phase. We report here the muon spin rotation and relaxation ($\mu$SR) measurements on the superconducting state of the topological Dirac semimetal PdTe2. From $\mu$SR measurements, we find that PdTe2 exhibits mixed type-I/type-II superconductivity. Using these results a phase diagram has been determined. In contrast to previous results where local type-II superconductivity persists up to Hc2 = 600 G, we observed that bulk superconductivity is destroyed above 225 G.

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D. Singh, Pabitra K. Biswas, Sungwon Yoon, C. H. Lee, A. D. Hillier, R. P. Singh, Amit Y. Singh, K. -Y. Choi. 2019-10-30. Coexistence of type-I and type-II superconductivity in topological superconductor PdTe$_2$. https://arxiv.org/abs/1910.13773

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