Floquet higher-order Weyl and nexus semimetals

Helical Spin Order from Topological Dirac and Weyl Semimetals.

We study dynamical mass generation and the resultant helical spin orders in topological Dirac and Weyl semimetals, including the edge states of quantum spin Hall insulators, the surface states of weak topological insulators, and the bulk materials of Weyl semimetals. In particular, the helical spin textures of Weyl semimetals manifest the spin-momentum locking of Weyl fermions in a visible mann...

Helicons in Weyl semimetals

Photocurrents in Weyl semimetals

Ching-Kit Chan,1 Netanel H. Lindner,2 Gil Refael,3 and Patrick A. Lee1 1Department of Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA 2Physics Department, Technion, 320003 Haifa, Israel 3Institute of Quantum Information and Matter and Department of Physics, California Institute of Technology, Pasadena, California 91125, USA (Received 13 August 2016; revised m...

Creating stable Floquet–Weyl semimetals by laser-driving of 3D Dirac materials

Tuning and stabilizing topological states, such as Weyl semimetals, Dirac semimetals or topological insulators, is emerging as one of the major topics in materials science. Periodic driving of many-body systems offers a platform to design Floquet states of matter with tunable electronic properties on ultrafast timescales. Here we show by first principles calculations how femtosecond laser pulse...

Electromagnetic response of Weyl semimetals.

It has been suggested recently, based on subtle field-theoretical considerations, that the electromagnetic response of Weyl semimetals and the closely related Weyl insulators can be characterized by an axion term θE·B with space and time dependent axion angle θ(r,t). Here we construct a minimal lattice model of the Weyl medium and study its electromagnetic response by a combination of analytica...