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Room temperature in-situ measurement of the spin voltage of a BiSbTe3 thin film.

ABSTRACT: One of the hallmarks of topological insulators (TIs), the intrinsic spin polarisation in the topologically protected surface states, is investigated at room temperature in-situ by means of four-probe scanning tunnelling microscopy (STM) for a BiSbTe3 thin film. To achieve the required precision of tip positions for measuring a spin signal, a precise positioning method employing STM scans of the local topography with each individual tip is demonstrated. From the transport measurements, the spin polarisation in the topological surface states (TSS) is estimated as p ~ 0.3 - 0.6, which is close to the theoretical limit.

SUBMITTER: Leis A

PROVIDER: S-EPMC7029040 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Room temperature in-situ measurement of the spin voltage of a BiSbTe3 thin film.

Leis Arthur A Schleenvoigt Michael M Jalil Abdur Rehman AR Cherepanov Vasily V Mussler Gregor G Grützmacher Detlev D Tautz F Stefan FS Voigtländer Bert B

Scientific reports 20200218 1

One of the hallmarks of topological insulators (TIs), the intrinsic spin polarisation in the topologically protected surface states, is investigated at room temperature in-situ by means of four-probe scanning tunnelling microscopy (STM) for a BiSbTe3 thin film. To achieve the required precision of tip positions for measuring a spin signal, a precise positioning method employing STM scans of the local topography with each individual tip is demonstrated. From the transport measurements, ...[more]

PMID: 32071388

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