Linear magnetoresistance caused by mobility fluctuations in the n-doped Cd3As2

TL;DR

This study investigates the origin of linear magnetoresistance in n-doped Cd3As2, attributing it to mobility fluctuations caused by disorder, and provides detailed experimental insights into its electronic properties at high magnetic fields.

Contribution

It demonstrates that the non-saturating linear magnetoresistance in Cd3As2 is likely due to disorder-induced mobility fluctuations, not Fermi surface changes, supported by high-field measurements and quantum oscillations.

Findings

Linear magnetoresistance persists up to 65T

Quantum oscillations reveal Dirac-like Fermi surface with Berry phase

High Zeeman splitting observed at strong magnetic fields

Abstract

Cd3As2 is a candidate three-dimensional Dirac semi-metal which has exceedingly high mobility and non-saturating linear magnetoresistance that may be relevant for future practical applications. We report magnetotransport and tunnel diode oscillation measurements on Cd3As2, in magnetic fields up to 65 T and temperatures between 1.5K to 300K. We find the non-saturating linear magnetoresistance persist up to 65T and it is likely caused by disorder effects as it scales with the high mobility, rather than directly linked to Fermi surface changes even when approaching the quantum limit. From the observed quantum oscillations, we determine the bulk three-dimensional Fermi surface having signatures of Dirac behaviour with non-trivial Berry's phase shift, very light effective quasiparticle masses and clear deviations from the band-structure predictions. In very high fields we also detect signatures of large Zeeman spin-splitting (g~16).