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Surface phonons in topological insulator Bi₂Te₃ investigated by Brillouin light scattering.

ABSTRACT: High resolution Brillouin spectroscopy was used for the first time to study the dispersion and anisotropy of surface phonons in the single crystal of topological insulator Bi₂Te₃. Two surface acoustic waves have been observed, which distinguishes this material from other metals or nontransparent materials. The modes were assigned as Rayleigh waves. The obtained results were then simulated by Finite Element Method. The layered structure of the unit cell proposed in simulation reproduced quite well experimental results of the modes dispersion and anisotropy.

SUBMITTER: Trzaskowska A

PROVIDER: S-EPMC7367295 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Surface phonons in topological insulator Bi2Te3 investigated by Brillouin light scattering.

Trzaskowska Aleksandra A Mroz Boguslaw B

Scientific reports 20200716 1

High resolution Brillouin spectroscopy was used for the first time to study the dispersion and anisotropy of surface phonons in the single crystal of topological insulator Bi2Te3. Two surface acoustic waves have been observed, which distinguishes this material from other metals or nontransparent materials. The modes were assigned as Rayleigh waves. The obtained results were then simulated by Finite Element Method. The layered structure of the unit cell proposed in simulatio ...[more]

PMID: 32678195

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