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Title: Tuning metal/superconductor to insulator/superconductor coupling via control of proximity enhancement between NbSe 2 monolayers
Abstract

The interplay between charge transfer and electronic disorder in transition-metal dichalcogenide multilayers gives rise to superconductive coupling driven by proximity enhancement, tunneling and superconducting fluctuations, of a yet unwieldy variety. Artificial spacer layers introduced with atomic precision change the density of states by charge transfer. Here, we tune the superconductive coupling betweenNbSe2monolayers from proximity-enhanced to tunneling-dominated. We correlate normal and superconducting properties inSnSe1+δmNbSe21tailored multilayers with varying SnSe layer thickness (m=115). From high-field magnetotransport the critical fields yield Ginzburg–Landau coherence lengths with an increase of140%cross-plane (m=19), trending towards two-dimensional superconductivity form>9. We show cross-overs between three regimes: metallic with proximity-enhanced coupling (m=14), disordered-metallic with intermediate coupling (m=59) and insulating with Josephson tunneling (m>9). Our results demonstrate that stacking metal mono- and dichalcogenides allows to convert a metal/superconductor into an insulator/superconductor system, prospecting the control of two-dimensional superconductivity in embedded layers.

 
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NSF-PAR ID:
10402899
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
Journal of Physics: Condensed Matter
Volume:
35
Issue:
21
ISSN:
0953-8984
Page Range / eLocation ID:
Article No. 215701
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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