Three-terminal Weyl complex with double surface arcs in a cubic lattice

Huang，Zhenqiao1,2; Chen，Zhongjia1,3; Zheng，Baobing1,4; Xu，Hu1,5

2020-12-01

10.1038/s41524-020-00354-y

npj Computational Materials   影响因子和分区

2057-3960

2057-3960

Exploring unconventional topological quasiparticles and their associated exotic physical properties has become a hot topic in condensed matter physics, thus stimulating extensive interest in recent years. Here, in contrast to the double-Weyl phonons (the topological chiral charge +2) in the trigonal and hexagonal crystal systems, we propose that the unconventional double-Weyl without counterparts in high-energy physics can emerge in the phonons of cubic structures, i.e., SrSi. Employing a two-band k ⋅ p Hamiltonian, we prove that the quadratic double-Weyl nodes are protected by the fourfold screw rotational symmetry C̃ . Strikingly, we find that the surface arcs are terminated with the Weyl nodes that possess unequal topological charges with opposite sign (i.e., +2 and −1), leading to unique three-terminal Weyl complex (one quadratic double-Weyl and two linear single-Weyl) with double surface arcs in SrSi. In addition, we apply a uniaxial tensile strain along z-axis to examine the evolution of the three-terminal Weyl complex when the corresponding symmetries are broken. Our work not only provides an ideal candidate for the realization of the quadratic double-Weyl and the corresponding unique surface arc states, but also broadens the understanding of topological Weyl physics.

SCI ; EI

英语

第一 ; 通讯

Guangdong Natural Science Funds for Distinguished Young Scholars[2017B030306008] ; National Natural Science Foundation of China[11974160][11674148][11334003] ; China Postdoctoral Science Foundation[2019M652686] ; Natural Science Basic Research Plan in Shaanxi Province of China[2018JQ1083]

Chemistry ; Materials Science

Chemistry, Physical ; Materials Science, Multidisciplinary

WOS:000548906000001

NATURE PUBLISHING GROUP

20202808905056

Phonons ; High energy physics ; Tensile strain ; Crystal structure

Combinatorial Mathematics, Includes Graph Theory, Set Theory:921.4 ; Mechanics:931.1 ; High Energy Physics:932.1 ; Crystal Lattice:933.1.1

2-s2.0-85087394879

Scopus

1.Department of Physics & Institute for Quantum Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China
2.Department of Physics,The Hong Kong University of Science and Technology,Clear Water Bay,Hong Kong
3.Department of Physics,South China University of Technology,Guangzhou,510640,China
4.College of Physics and Optoelectronic Technology & Advanced Titanium Alloys and Functional Coatings Cooperative Innovation Center,Baoji University of Arts and Sciences,Baoji,721016,China
5.Guangdong Provincial Key Laboratory of Computational Science and Material Design,Southern University of Science and Technology,Shenzhen,518055,China

Huang，Zhenqiao,Chen，Zhongjia,Zheng，Baobing,et al. Three-terminal Weyl complex with double surface arcs in a cubic lattice[J]. npj Computational Materials,2020,6(1).

Huang，Zhenqiao,Chen，Zhongjia,Zheng，Baobing,&Xu，Hu.(2020).Three-terminal Weyl complex with double surface arcs in a cubic lattice.npj Computational Materials,6(1).

Huang，Zhenqiao,et al."Three-terminal Weyl complex with double surface arcs in a cubic lattice".npj Computational Materials 6.1(2020).