Materials design from non-equilibrium steady states: driven graphene as a tunable semiconductor with topological properties

Abstract

Controlling the properties of materials by driving them out of equilibrium is an exciting prospect that has only recently begun to be explored. In this paper we give a striking theoretical example of such materials design: a tunable gap in monolayer graphene is generated by exciting a particular optical phonon. We show that the system reaches a steady state whose transport properties are the same as if the system had a static electronic gap, controllable by the driving amplitude. Moreover, the steady state displays topological phenomena: there are chiral edge currents, which circulate a fractional charge e/2 per rotation cycle, with frequency set by the optical phonon frequency.

Edited version; minor corrections

References in corpus (7)

• Superconducting proximity effect and Majorana fermions at the surface of a topological insulator
• Electrodynamics of Correlated Electron Materials
• Electron fractionalization in two-dimensional graphenelike structures
• Chiral Gauge Theory for Graphene
• Electron fractionalization for two-dimensional Dirac fermions
• Vortices, zero modes and fractionalization in bilayer-graphene exciton condensate
• Persistence of zero modes in a gauged Dirac model for bilayer graphene