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Title: Crossover from Conventional to Unconventional Superconductivity in 2M-WS 2
Leveraging the reciprocal-space proximity effect between superconducting bulk and topological surface states (TSSs) offers a promising way to topological superconductivity. However, elucidating the mutual influence of bulk and TSSs on topological superconductivity remains a challenge. Here, we report pioneering transport evidence of a thickness-dependent transition from conventional to unconventional superconductivity in 2M-phase WS2 (2M-WS2). As the sample thickness reduces, we see clear changes in key superconducting metrics, including critical temperature, critical current, and carrier density. Notably, while thick 2M-WS2 samples show conventional superconductivity, with an in-plane (IP) upper critical field constrained by the Pauli limit, samples under 20 nm exhibit a pronounced IP critical field enhancement, inversely correlated with 2D carrier density. This marks a distinct crossover to unconventional superconductivity with strong spin-orbit-parity coupling. Our findings underscore the crucial role of sample thickness in accessing topological states in 2D topological superconductors, offering pivotal insights into future studies of topological superconductivity.  more » « less
Award ID(s):
2228841
PAR ID:
10628389
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
ACS
Date Published:
Journal Name:
Nano Letters
Volume:
24
Issue:
50
ISSN:
1530-6984
Page Range / eLocation ID:
16184 to 16190
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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