Floquet interface states in illuminated three dimensional topological insulators

HERNAN L. CALVO; LUIS E. F. FOA TORRES; PABLO M. PEREZ-PISKUNOW; CARLOS A. BALSEIRO; GONZALO USAJ

PHYSICAL REVIEW B

AMER PHYSICAL SOC

Lugar: New York; Año: 2015 vol. 91 p. 241404 - 241404

1098-0121

Recent experiments showed that the surface of a three dimensional topological insulator develops gaps in the Floquet-Bloch band spectrum when illuminated with a circularly polarized laser. These Floquet-Bloch bands are characterized by non-trivial Chern numbers which only depend on the helicity of the polarization of the radiation field. Here we propose a setup consisting of a pair of counter-rotating lasers, and show that one-dimensional chiral states emerge at the interface between the two lasers. These interface states turn out to be spin-polarized and may trigger interesting applications in the field of optoelectronics and spintronics.