Quantum oscillations of magnetoresistance of the submicrometer thick bismuth telluride-based films

TL;DR

This study investigates quantum oscillations in magnetoresistance of bismuth telluride films, revealing topological surface states with potential applications in micro devices.

Contribution

It provides experimental evidence of topological Dirac surface states in bismuth telluride films through magnetoresistance oscillation analysis.

Findings

Quantum oscillations observed below 10 K in magnetic fields 6-14 T.

Landau level analysis confirms Berry phase characteristic of topological states.

Electronic surface state parameters estimated for potential device applications.

Abstract

Hetero-epitaxial films based on bismuth telluride with excess of Te were grown by hat wall technique at the surface of the mica (muscovite). Galvanomagnetic properties of the thin films were measured, and quantum oscillations of the magnetoresistance were found at the temperatures below 10 K in the magnetic field from 6 to 14 T. From analysis of magnetoresistance oscillations the main surface state parameters of the films were determined. Expementally obtained Landau level index shift and its temperature dependence are consistent with Berry phase specific for topological Dirac surface states. The estimated parameters of electronic topological surface states of the bismuth telluride-based films are of special interest because of possible usage of them in micro generators and micro coolers, and also for other device applications.