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Title: Superconductor–insulator transition in two-dimensional indium–indium-oxide composite

The magnetic-field–tuned superconductor-to-insulator transition was studied in a hybrid system of superconducting indium islands, deposited on an indium oxide (InOx) thin film, which exhibits global superconductivity at low magnetic fields. Vacuum annealing was used to tune the conductivity of the InOx film, thereby tuning the inergrain coupling and the nature of the transition. The hybrid system exhibits a “giant” magnetoresistance above the magnetic-field–tuned superconductor-to-insulator transition (H-SIT), with critical behavior similar to that of uniform InOx films but at much lower magnetic fields, that manifests the duality between Cooper pairs and vortices. A key feature of this hybrid system is the separation between the quantum criticality and the onset of nonequilibrium behavior.

Authors:
; ; ; ;
Award ID(s):
1808385
Publication Date:
NSF-PAR ID:
10208148
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
118
Issue:
2
Page Range or eLocation-ID:
Article No. e2015970118
ISSN:
0027-8424
Publisher:
Proceedings of the National Academy of Sciences
Sponsoring Org:
National Science Foundation
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