Higher-Order Weyl Semimetals

Abstract

Higher-order topology yields intriguing multidimensional topological phenomena, while Weyl semimetals have unconventional properties such as chiral anomaly. However, so far, Weyl physics remain disconnected with higher-order topology. Here, we report the theoretical discovery of higher-order Weyl points and thereby the establishment of such an important connection. We demonstrate that higher-order Weyl points can emerge in chiral materials such as chiral tetragonal crystals as the intermediate phase between the conventional Weyl semimetal and 3D higher-order topological phases. Higher-order Weyl semimetals manifest themselves uniquely by exhibiting concurrent chiral Fermi-arc surface states, topological hinge states, and the momentum-dependent fractional hinge charge, revealing a novel class of higher-order topological phases.

4+ pages, 4 figures

References in corpus (9)

• Electric Multipole Moments, Topological Multipole Moment Pumping, and Chiral Hinge States in Crystalline Insulators
• $(d-2)$-dimensional edge states of rotation symmetry protected topological states
• Reflection symmetric second-order topological insulators and superconductors
• Higher-order topological insulators and semimetals on the breathing Kagome and pyrochlore lattices
• Visualization of higher-order topological insulating phases in two-dimensional dielectric photonic crystals
• Direct observation of corner states in second-order topological photonic crystal slabs
• Photonic crystal nanocavity based on a topological corner state
• Acoustic realization of quadrupole topological insulators
• Plasmon-polaritonic quadrupole topological insulators

Cited by in corpus (9)

• Hybrid-order topological insulators in a phononic crystal
• Second-Order Real Nodal-Line Semimetal in Three-Dimensional Graphdiyne
• Acoustic Higher-Order Weyl Semimetal with Bound Hinge States in the Continuum
• Field-Tunable One-Sided Higher-Order Topological Hinge States in Dirac Semimetals
• Filling anomaly for general 2D and 3D $C_4$ symmetric lattices
• Non-Hermitian Weyl semimetal and its Floquet engineering
• Topological States in Two-Dimensional Su-Schrieffer-Heeger Models
• Topolectrical-circuit realization of quadrupolar surface semimetals
• Type-II Weyl Excitation in Vortex Arrays