Ultrahigh mobility and giant magnetoresistance in the Dirac semimetal Cd3As2

Tian Liang; Quinn Gibson; Mazhar N Ali; Minhao Liu; R J Cava; N P Ong

doi:10.1038/nmat4143

Ultrahigh mobility and giant magnetoresistance in the Dirac semimetal Cd3As2

Nat Mater. 2015 Mar;14(3):280-4. doi: 10.1038/nmat4143. Epub 2014 Nov 24.

Authors

Tian Liang¹, Quinn Gibson², Mazhar N Ali², Minhao Liu¹, R J Cava², N P Ong¹

Affiliations

¹ Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.
² Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.

PMID: 25419815
DOI: 10.1038/nmat4143

Abstract

Dirac and Weyl semimetals are 3D analogues of graphene in which crystalline symmetry protects the nodes against gap formation. Na3Bi and Cd3As2 were predicted to be Dirac semimetals, and recently confirmed to be so by photoemission experiments. Several novel transport properties in a magnetic field have been proposed for Dirac semimetals. Here, we report a property of Cd3As2 that was unpredicted, namely a remarkable protection mechanism that strongly suppresses backscattering in zero magnetic field. In single crystals, the protection results in ultrahigh mobility, 9 × 10(6) cm(2) V(-1) s(-1) at 5 K. Suppression of backscattering results in a transport lifetime 10(4) times longer than the quantum lifetime. The lifting of this protection by the applied magnetic field leads to a very large magnetoresistance. We discuss how this may relate to changes to the Fermi surface induced by the applied magnetic field.