Large linear magnetoresistance in Dirac semi-metal Cd3As2 with Fermi surfaces close to the Dirac points

TL;DR

This study reports a large linear magnetoresistance in high-quality Cd3As2 Dirac semi-metal crystals, linked to field-induced Fermi surface distortions, with potential implications for electronic applications.

Contribution

It demonstrates a significant linear magnetoresistance in Cd3As2 and proposes a mechanism involving Fermi surface distortion caused by magnetic fields.

Findings

Magnetoresistance as high as 3100% at 14 T

Large LMR occurs with magnetic field perpendicular to current and surface

LMR diminishes with tilting field or increasing temperature

Abstract

We have investigated the magnetoresistive behavior of Dirac semi-metal Cd3As2 down to low temperatures and in high magnetic fields. A positive and linear magnetoresistance (LMR) as large as 3100% is observed in a magnetic field of 14 T, on high-quality single crystals of Cd3As2 with ultra-low electron density and large Lande g factor. Such a large LMR occurs when the magnetic field is applied perpendicular to both the current and the (100) surface, and when the temperature is low such that the thermal energy is smaller than the Zeeman splitting energy. Tilting the magnetic field or raising the temperature all degrade the LMR, leading to a less pronounced quadratic behavior. We propose that the phenomenon of LMR is related to the peculiar field-induced shifting/distortion of the helical electrons' Fermi surfaces in momentum space.