Floquet topological magnons

Abstract

We introduce the concept of Floquet topological magnons—a mechanism by which a synthetic tunable Dzyaloshinskii–Moriya interaction (DMI) can be generated in quantum magnets using circularly polarized electric (laser) field. The resulting effect is that Dirac magnons and nodal-line magnons in two-dimensional and three-dimensional quantum magnets can be tuned to magnon Chern insulators and Weyl magnons respectively under circularly polarized laser field. The Floquet formalism also yields a tunable intrinsic DMI in insulating quantum magnets without an inversion center. We demonstrate that the Floquet topological magnons possess a finite thermal Hall conductivity tunable by the laser field.