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Title: Unusual superconductivity in the topological nodal-line semimetal candidate Sn x NbSe 2-δ
Abstract We report the superconductivity of the topological nodal-line semimetal candidate Sn x NbSe 2- δ with a noncentrosymmetric crystal structure. The superconducting transition temperature T c of Sn x NbSe 2- δ drastically varies with the Sn concentration x and the Se deficiency δ , and reaches 12 K, relatively higher than those of known topological superconductors. The upper critical field of this compound shows unusual temperature dependence, inconsistent with the WHH theory for conventional type-II superconductors. In a low-T c sample, the zero-temperature limit of the upper critical field parallel to the ab plane exceeds the Pauli paramagnetic limit estimated from the simple BCS weak coupling model by a factor of ∼ 2, suggestive of unusual superconductivity stabilized in Sn x NbSe 2- δ . Together with the robust superconductivity against disorder, these observations indicate that Sn x NbSe 2- δ is a promising candidate to explore topological superconductivity.  more » « less
Award ID(s):
1944975
PAR ID:
10326010
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Physics: Conference Series
Volume:
2164
Issue:
1
ISSN:
1742-6588
Page Range / eLocation ID:
012008
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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