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Title: Observation of a Majorana zero mode in a topologically protected edge channel

Journal Article · · Science

Superconducting proximity pairing in helical edge modes, such as those of topological insulators, is predicted to provide a unique platform for realizing Majorana zero modes (MZMs). We used scanning tunneling microscopy measurements to probe the influence of proximity-induced superconductivity and magnetism on the helical hinge states of bismuth(111) films grown on a superconducting niobium substrate and decorated with magnetic iron clusters. Consistent with model calculations, our measurements revealed the emergence of a localized MZM at the interface between the superconducting helical edge channel and the iron clusters, with a strong magnetization component along the edge. Our experiments also resolve the MZM’s spin signature, which distinguishes it from trivial in-gap states that may accidentally occur at zero energy in a superconductor.

Sponsoring Organization:
USDOE
Grant/Contract Number:
SC0016239
OSTI ID:
1529747
Alternate ID(s):
OSTI ID: 1612437
Journal Information:
Science, Journal Name: Science Journal Issue: 6447 Vol. 364; ISSN 0036-8075
Publisher:
American Association for the Advancement of Science (AAAS)Copyright Statement
Country of Publication:
United States
Language:
English

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