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  • Signatures of a spin-active interface and a locally enhanced Zeeman field in a superconductor-chiral material heterostructure
Title: Signatures of a spin-active interface and a locally enhanced Zeeman field in a superconductor-chiral material heterostructure
A localized Zeeman field, intensified at heterostructure interfaces, could play a crucial role in a broad area including spintronics and unconventional superconductors. Conventionally, the generation of a local Zeeman field is achieved through magnetic exchange coupling with a magnetic material. However, magnetic elements often introduce defects, which could weaken or destroy superconductivity. Alternatively, the coupling between a superconductor with strong spin-orbit coupling and a nonmagnetic chiral material could serve as a promising approach to generate a spin-active interface. Here, we leverage an interface superconductor, namely, induced superconductivity in noble metal surface states, to probe the spin-active interface. Our results unveil an enhanced interface Zeeman field, which selectively closes the surface superconducting gap while preserving the bulk superconducting pairing. The chiral material, i.e., trigonal tellurium, also induces Andreev bound states (ABS) exhibiting spin polarization. The field dependence of ABS manifests a substantially enhanced interface Landég-factor (geff~ 12), thereby corroborating the enhanced interface Zeeman energy.  more » « less
Award ID(s):
2046648 2040620
PAR ID:
10581068
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
American Association for the Advancement of Science (AAAS)
Date Published:
Journal Name:
Science Advances
Volume:
10
Issue:
34
ISSN:
2375-2548
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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