Granularity Controlled Non-Saturating Linear Magneto-resistance in Topological Insulator Bi2Te3 Films

TL;DR

This study investigates the linear magneto-resistance in granular Bi2Te3 topological insulator films, revealing a universal correlation with mobility and attributing the effect to mobility fluctuations, with implications for fundamental physics and device applications.

Contribution

The paper demonstrates that granularity controls the LMR in Bi2Te3 films and links it to mobility fluctuations, expanding understanding of magneto-transport in topological insulators.

Findings

LMR magnitude correlates with average mobility over two orders of magnitude.

The LMR effect is attributed to mobility fluctuation-induced classical LMR.

Granularity influences the magneto-transport properties of Bi2Te3 films.

Abstract

We report on the magneto-transport properties of chemical vapor deposition grown films of interconnected Bi2Te3 nanoplates. Similar to many other topological insulator (TI) materials, these granular Bi2Te3 films exhibit a linear magneto-resistance (LMR) effect which has received much recent attention. Studying samples with different degree of granularity, we find a universal correlation between the magnitude of the LMR and the average mobility (<\mu>) of the films over nearly two orders of magnitude change of <\mu>. The granularity controlled LMR effect here is attributed to the mobility fluctuation induced classical LMR according to the Parish-Littlewood theory. These findings have implications to both the fundamental understanding and magneto-resistive device applications of TI and small bandgap semiconductor materials.