Recipe for Dirac Phonon States with a Quantized Valley Berry Phase in Two-Dimensional Hexagonal Lattices

Jin, Yuanjun1,2; Wang, Rui1,2,3,4; Xu, Hu1,2

2018-12

10.1021/acs.nanolett.8b03492

NANO LETTERS   影响因子和分区

1530-6984

1530-6992

The topological quantum states in two-dimensional (2D) materials are fascinating subjects of research, which usually highlight electron-related systems. In this work, we present a recipe that leads to Dirac phonon states with a quantized valley Berry phase in 2D hexagonal lattices by first principles calculations. We show that candidates possessing the 3-fold rotational symmetry at the corners of the hexagonal Brillouin zone host valley Dirac phonons, which are guaranteed to remain intact with respect to perturbations. We identify that such special topological features populated by Dirac phonons can be realized in various 2D materials. In particular, the monolayer CrI3, an attractive 2D magnetic semiconductor with exotic applications in spintronics, is an ideal platform to investigate nontrivial phonons in experiments. We further confirm that the phonon Berry phase is quantized to +/- pi at two inequivalent valleys. The phonon edge states terminated at the projection of phonon Dirac cones are clearly visible. This work demonstrates that 2D hexagonal lattices with attractive valley Dirac phonons will extend the knowledge of valley physics, providing wide applications of topological phonons.

Dirac phonons valley Berry phase phonon edge states 2D hexagonal lattices first-principles calculations

SCI ; EI

英语

NI期刊

第一 ; 通讯

Science Challenge Project[TZ2016003]

Chemistry ; Science & Technology - Other Topics ; Materials Science ; Physics

Chemistry, Multidisciplinary ; Chemistry, Physical ; Nanoscience & Nanotechnology ; Materials Science, Multidisciplinary ; Physics, Applied ; Physics, Condensed Matter

WOS:000453488800044

AMER CHEMICAL SOC

20184906204234

Calculations ; Crystal lattices ; Fruits ; Landforms ; Magnetic semiconductors ; Quantum theory ; Topology

Geology:481.1 ; Magnetic Materials:708.4 ; Agricultural Products:821.4 ; Mathematics:921 ; Combinatorial Mathematics, Includes Graph Theory, Set Theory:921.4 ; Quantum Theory; Quantum Mechanics:931.4 ; Crystal Lattice:933.1.1

MATERIALS SCIENCE

Web of Science

1.Southern Univ Sci & Technol, Dept Phys, Shenzhen 518055, Peoples R China
2.Southern Univ Sci & Technol, Inst Quantum Sci & Engn, Shenzhen 518055, Peoples R China
3.Chongqing Univ, Inst Struct & Funct, Chongqing 400044, Peoples R China
4.Chongqing Univ, Dept Phys, Chongqing 400044, Peoples R China

Jin, Yuanjun,Wang, Rui,Xu, Hu. Recipe for Dirac Phonon States with a Quantized Valley Berry Phase in Two-Dimensional Hexagonal Lattices[J]. NANO LETTERS,2018,18(12):7755-7760.

Jin, Yuanjun,Wang, Rui,&Xu, Hu.(2018).Recipe for Dirac Phonon States with a Quantized Valley Berry Phase in Two-Dimensional Hexagonal Lattices.NANO LETTERS,18(12),7755-7760.

Jin, Yuanjun,et al."Recipe for Dirac Phonon States with a Quantized Valley Berry Phase in Two-Dimensional Hexagonal Lattices".NANO LETTERS 18.12(2018):7755-7760.