Josephson Effect and Charge Distribution in Thin Bi$_2$Te$_3$ Topological Insulators

TL;DR

This study investigates the Josephson effect and charge distribution in thin Bi$_2$Te$_3$ topological insulators, combining experimental measurements with self-consistent modeling to understand carrier behavior and transport phenomena.

Contribution

It provides a quantitative analysis of carrier distribution and transport in thin Bi$_2$Te$_3$ films using combined experimental and theoretical approaches, with no ad hoc assumptions.

Findings

Excellent agreement between experimental data and Schrödinger-Poisson model

Quantitative interpretation of weak anti-localization effects

Understanding of critical current behavior in Josephson junctions

Abstract

Thin layers of topological insulator materials are quasi-two-dimensional systems featuring a complex interplay between quantum confinement and topological band structure. To understand the role of the spatial distribution of carriers in electrical transport, we study the Josephson effect, magnetotransport, and weak anti-localization in bottom-gated thin Bi$_2$Te$_3$ topological insulator films.We compare the experimental carrier densities to a model based on the solutions of the self-consistent Schr\"odinger-Poisson equations and find excellent agreement. The modeling allows for a quantitative interpretation of the weak antilocalization correction to the conduction and of the critical current of Josephson junctions with weak links made from such films without any ad hoc assumptions.