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The electron-phonon interaction at deep Bi 2 Te3-semiconductor interfaces from Brillouin light scattering.

ABSTRACT: It is shown that the electron-phonon interaction at a conducting interface between a topological insulator thin film and a semiconductor substrate can be directly probed by means of high-resolution Brillouin light scattering (BLS). The observation of Kohn anomalies in the surface phonon dispersion curves of a 50?nm thick Bi2Te3 film on GaAs, besides demonstrating important electron-phonon coupling effects in the GHz frequency domain, shows that information on deep interface electrons can be obtained by tuning the penetration depth of optically-generated surface phonons so as to selectively probe the interface region, as in a sort of quantum sonar.

SUBMITTER: Wiesner M

PROVIDER: S-EPMC5703879 | biostudies-other | 2017 Nov

REPOSITORIES: biostudies-other

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The electron-phonon interaction at deep Bi 2 Te3-semiconductor interfaces from Brillouin light scattering.

Wiesner M M Trzaskowska A A Mroz B B Charpentier S S Wang S S Song Y Y Lombardi F F Lucignano P P Benedek G G Campi D D Bernasconi M M Guinea F F Tagliacozzo A A

Scientific reports 20171127 1

It is shown that the electron-phonon interaction at a conducting interface between a topological insulator thin film and a semiconductor substrate can be directly probed by means of high-resolution Brillouin light scattering (BLS). The observation of Kohn anomalies in the surface phonon dispersion curves of a 50 nm thick Bi2Te3 film on GaAs, besides demonstrating important electron-phonon coupling effects in the GHz frequency domain, shows that information on deep interface ...[more]

PMID: 29180657

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