Quantum electrical transport properties of topological insulator Bi2Te3 nanowires

TL;DR

This study explores the quantum transport behavior of surface electrons in Bi2Te3 nanowires, revealing clear Aharonov-Bohm oscillations and temperature-dependent phase coherence, advancing understanding of topological insulator nanostructures.

Contribution

It demonstrates the observation of quantum interference effects and analyzes phase coherence in Bi2Te3 nanowires using magnetotransport measurements and localization theory.

Findings

Observation of Aharonov-Bohm oscillations with phases 0 and pi

Exponential temperature dependence of oscillation amplitude

Extraction of surface contribution supporting phase coherence analysis

Abstract

We investigate the quantum transport properties of surface electrons on a topological insulator Bi2Te3 nanowire in a magnetotransport study. Although the nanowires are synthesized by using a relatively coarse method of electrochemical deposition, clear Aharonov-Bohm oscillations of phases 0 and pi are observed, owing to the highly coherent surface electron channel. The oscillation amplitude exhibits exponential temperature dependence, suggesting that the phase coherence length L_phi is inversely proportional to the temperature, as in quasi-ballistic systems. In addition, a weak antilocalization analysis on the surface channel by using a one-dimensional localization theory, enabled by successful extraction of the surface contribution from the magnetoconductance data, is provided in support of the temperature dependence of L_phi.