A double-Weyl semimetal stabilized by screw symmetry. (October 2019)

• Record Type: Journal Article
• Authors: Luo, Wei; Wang, Xiaohui; Deng, Ming-Xun
• Is Part Of: Solid state communications. Volume 300(2019)
• Publication Date: 2019-10
• Subjects: Double-Weyl semimetals -- Band crossings -- Screw symmetry -- Quadratic dispersion; Solid state chemistry -- Periodicals; Solid state physics -- Periodicals; Chimie de l'état solide -- Périodiques; Physique de l'état solide -- Périodiques; 530.41
• DOI: 10.1016/j.ssc.2019.113693
• Languages: English
• ISSNs: 0038-1098

Abstract

Abstract: We investigate a double-Weyl semimetal stabilized by screw symmetry T ẑ C 4, with C 4 the fourfold rotation around the z axis, and T ẑ a translation operation along z direction. It is found that the screw symmetry T ẑ C 4 guarantees that the dispersion relation is quadratic near the double-Weyl nodes by symmetry analysis. The form of the low-energy effective Hamiltonian near the double-Weyl nodes can be completely determined by symmetries of the system. We also investigate the symmetry-breaking effect. When a symmetry breaking term is added to the system, each double-Weyl node splits into two linear Weyl nodes with monopole charge ±1. The symmetry-breaking effect can be seen from the Fermi arcs.