Observation of a three-dimensional topological Dirac semimetal phase in high-mobility Cd3As2

Madhab Neupane; Su-Yang Xu; Raman Sankar; Nasser Alidoust; Guang Bian; Chang Liu; Ilya Belopolski; Tay-Rong Chang; Horng-Tay Jeng; Hsin Lin; Arun Bansil; Fangcheng Chou; M Zahid Hasan

doi:10.1038/ncomms4786

Observation of a three-dimensional topological Dirac semimetal phase in high-mobility Cd3As2

Nat Commun. 2014 May 7:5:3786. doi: 10.1038/ncomms4786.

Authors

Madhab Neupane¹, Su-Yang Xu¹, Raman Sankar², Nasser Alidoust³, Guang Bian³, Chang Liu³, Ilya Belopolski³, Tay-Rong Chang⁴, Horng-Tay Jeng⁵, Hsin Lin⁶, Arun Bansil⁷, Fangcheng Chou⁸, M Zahid Hasan⁹

Affiliations

¹ 1] Joseph Henry Laboratory, Department of Physics, Princeton University, Princeton, New Jersey 08544, USA [2].
² 1] Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan [2].
³ Joseph Henry Laboratory, Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.
⁴ Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan.
⁵ 1] Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan [2] Institute of Physics, Academia Sinica, Taipei 11529, Taiwan.
⁶ Graphene Research Centre, Department of Physics, National University of Singapore, Singapore 117542, Singapore.
⁷ Department of Physics, Northeastern University, Boston, Massachusetts 02115, USA.
⁸ Center for Condensed Matter Sciences, National Taiwan University, Taipei 10617, Taiwan.
⁹ 1] Joseph Henry Laboratory, Department of Physics, Princeton University, Princeton, New Jersey 08544, USA [2] Princeton Center for Complex Materials, Princeton University, Princeton, New Jersey 08544, USA.

PMID: 24807399
DOI: 10.1038/ncomms4786

Abstract

Symmetry-broken three-dimensional (3D) topological Dirac semimetal systems with strong spin-orbit coupling can host many exotic Hall-like phenomena and Weyl fermion quantum transport. Here, using high-resolution angle-resolved photoemission spectroscopy, we performed systematic electronic structure studies on Cd3As2, which has been predicted to be the parent material, from which many unusual topological phases can be derived. We observe a highly linear bulk band crossing to form a 3D dispersive Dirac cone projected at the Brillouin zone centre by studying the (001)-cleaved surface. Remarkably, an unusually high in-plane Fermi velocity up to 1.5×10(6) ms(-1) is observed in our samples, where the mobility is known up to 40,000 cm2 V(-1) s(-1), suggesting that Cd3As2 can be a promising candidate as an anisotropic-hypercone (three-dimensional) high spin-orbit analogue of 3D graphene. Our discovery of the Dirac-like bulk topological semimetal phase in Cd3As2 opens the door for exploring higher dimensional spin-orbit Dirac physics in a real material.

Publication types

Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.