Weak Antilocalization and Conductance Fluctuation in a Sub-micrometer-sized Wire of Epitaxial Bi2Se3

TL;DR

This paper investigates phase coherent transport phenomena, specifically weak antilocalization and conductance fluctuations, in a sub-micrometer Bi2Se3 wire, revealing quasi-one-dimensional electron conduction at low temperatures.

Contribution

It provides experimental evidence of phase coherence effects in a narrow Bi2Se3 wire and confirms the quasi-one-dimensional conduction through combined WAL and conductance fluctuation analysis.

Findings

WAL effect well described by Hikami-Larkin-Nagaoka model

Temperature dependence indicates quasi-one-dimensional conduction

Coherence length from conductance fluctuation matches WAL analysis

Abstract

In this study, we address the phase coherent transport in a sub-micrometer-sized Hall bar made of epitaxial Bi2Se3 thin film by probing the weak antilocalization (WAL) and the magnetoresistance fluctuation below 22 K. The WAL effect is well described by the Hikami-Larkin-Nagaoka model, where the temperature dependence of the coherence length indicates that electron conduction occurs quasi-one-dimensionally in the narrow Hall bar. The temperature-dependent magnetoresistance fluctuation is analyzed in terms of the universal conductance fluctuation, which gives a coherence length consistent with that derived from the WAL effect.