Realization of unpinned two-dimensional dirac states in antimony atomic layers

Qiangsheng Lu; Jacob Cook; Xiaoqian Zhang; Kyle Y Chen; Matthew Snyder; Duy Tung Nguyen; P V Sreenivasa Reddy; Bingchao Qin; Shaoping Zhan; Li-Dong Zhao; Pawel J Kowalczyk; Simon A Brown; Tai-Chang Chiang; Shengyuan A Yang; Tay-Rong Chang; Guang Bian

doi:10.1038/s41467-022-32327-8

Realization of unpinned two-dimensional dirac states in antimony atomic layers

Nat Commun. 2022 Aug 6;13(1):4603. doi: 10.1038/s41467-022-32327-8.

Authors

Qiangsheng Lu¹, Jacob Cook¹, Xiaoqian Zhang¹, Kyle Y Chen², Matthew Snyder¹, Duy Tung Nguyen¹, P V Sreenivasa Reddy³, Bingchao Qin⁴, Shaoping Zhan⁴, Li-Dong Zhao⁴, Pawel J Kowalczyk⁵, Simon A Brown⁶, Tai-Chang Chiang^{7

8}, Shengyuan A Yang⁹, Tay-Rong Chang³, Guang Bian¹⁰

Affiliations

¹ Department of Physics and Astronomy, University of Missouri, Columbia, MO, 65211, USA.
² Rock Bridge High School, Columbia, MO, 65203, USA.
³ Department of Physics, National Cheng Kung University, Tainan, 701, Taiwan.
⁴ School of Materials Science and Engineering, Beihang University, Beijing, 100191, China.
⁵ Department of Solid State Physics, Faculty of Physics and Applied Informatics, University of Lodz, 90-236 Lodz, Pomorska, 149/153, Poland. pawel.kowalczyk@uni.lodz.pl.
⁶ The MacDiarmid Institute for Advanced Materials and Nanotechnology, School of Physical and Chemical Sciences, University of Canterbury, Private Bag 4800, Christchurch, 8140, New Zealand.
⁷ Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL, 61801-3080, USA.
⁸ Frederick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, 104 South Goodwin Avenue, Urbana, IL, 61801-2902, USA.
⁹ Research Laboratory for Quantum Materials, Singapore University of Technology and Design, Singapore, 487372, Singapore.
¹⁰ Department of Physics and Astronomy, University of Missouri, Columbia, MO, 65211, USA. biang@missouri.edu.

Abstract

Two-dimensional (2D) Dirac states with linear dispersion have been observed in graphene and on the surface of topological insulators. 2D Dirac states discovered so far are exclusively pinned at high-symmetry points of the Brillouin zone, for example, surface Dirac states at [Formula: see text] in topological insulators Bi₂Se(Te)₃ and Dirac cones at K and [Formula: see text] points in graphene. The low-energy dispersion of those Dirac states are isotropic due to the constraints of crystal symmetries. In this work, we report the observation of novel 2D Dirac states in antimony atomic layers with phosphorene structure. The Dirac states in the antimony films are located at generic momentum points. This unpinned nature enables versatile ways such as lattice strains to control the locations of the Dirac points in momentum space. In addition, dispersions around the unpinned Dirac points are highly anisotropic due to the reduced symmetry of generic momentum points. The exotic properties of unpinned Dirac states make antimony atomic layers a new type of 2D Dirac semimetals that are distinct from graphene.

Grants and funding

NSF DMR-1809160/National Science Foundation (NSF)