2019/05/11 by S. A. Sato, J. W. McIver, M. Nuske +9 · 3 citations
Physics and Astronomy · #cond-mat.mes-hall #physics.optics
paper · pdf · doi:10.1103/physrevb.99.214302
published as Phys. Rev. B 99, 214302 (2019)
arxiv created 2019/05/11 · arxiv updated 2019/06/19
We employ a quantum Liouville equation with relaxation to model the recently observed anomalous Hall effect in graphene irradiated by an ultrafast pulse of circularly polarized light. In the weak-field regime, we demonstrate that the Hall effect originates from an asymmetric population of photocarriers in the Dirac bands. By contrast, in the strong-field regime, the system is driven into a non-equilibrium steady state that is well-described by topologically non-trivial Floquet-Bloch bands. Here, the anomalous Hall current originates from the combination of a population imbalance in these dressed bands together with a smaller anomalous velocity contribution arising from their Berry curvature. This robust and general finding enables the simulation of electrical transport from light-induced Floquet-Bloch bands in an experimentally relevant parameter regime and creates a pathway to designing ultrafast quantum devices with Floquet-engineered transport properties.