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Topological Quantum Well States in Pb/Sb Thin-Film Heterostructures.

ABSTRACT: Composite topological heterostructures, wherein topologically protected states are electronically tuned due to their proximity to other matter, are key avenues for exploring emergent physical phenomena. Particularly, pairing a topological material with a superconductor such as Pb is a promising means for generating a topological superconducting phase with exotic Majorana quasiparticles, but oft-neglected is the emergence of bulklike spin-polarized states that are quite relevant to applications. Using high-resolution photoemission spectroscopy and first-principles calculations, we report the emergence of bulk-like spin-polarized topological quantum well states with long coherence lengths in Pb films grown on the topological semimetal Sb. The results establish Pb/Sb heterostructures as topological superconductor candidates and advance the current understanding of topological coupling effects required for realizing emergent physics and for designing advanced spintronic device architectures.

SUBMITTER: Li Y

PROVIDER: S-EPMC11008363 | biostudies-literature | 2024 Apr

REPOSITORIES: biostudies-literature

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Topological Quantum Well States in Pb/Sb Thin-Film Heterostructures.

Li Yao Y Chan Yang-Hao YH Hlevyack Joseph A JA Bowers John W JW Chou Mei-Yin MY Chiang Tai-Chang TC

ACS nano 20240326 14

Composite topological heterostructures, wherein topologically protected states are electronically tuned due to their proximity to other matter, are key avenues for exploring emergent physical phenomena. Particularly, pairing a topological material with a superconductor such as Pb is a promising means for generating a topological superconducting phase with exotic Majorana quasiparticles, but oft-neglected is the emergence of bulklike spin-polarized states that are quite relevant to applications. ...[more]

PMID: 38530641

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