Optically engineering the topological properties of helical edge states

ORAL

Abstract

Time-periodic perturbations can be used to engineer topological properties of matter by altering the Floquet band structure. This is demonstrated for the helical edge state of a spin Hall insulator in the presence of monochromatic circularly polarized light. We first demonstrate that the inherent spin structure of the edge state is influenced by the Zeeman coupling and not by the orbital effect. The photocurrent (and the magnetization along the edge) develops a finite, helicity dependent expectation value and turns from dissipationless to dissipative with increasing radiation frequency, signalling a change in the topological properties. The connection with Thouless' charge pumping and non-equilibrium Zitterbewegung is discussed, together with possible experiments. B. Dora, J. Cayssol, F. Simon, and R. Moessner, Optically engineering the topological properties of a spin Hall insulator, arXiv:1105.5963

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Authors

  • Jerome Cayssol

    LOMA, University Bordeaux-1, France, Max-Planck-Institut f\"ur Physik komplexer Systeme, N\"othnitzer Str. 38, 01187 Dresden, Germany, LOMA (UMR-5798), CNRS and University Bordeaux, F-33045 Talence, France

  • Bal\'azs D\'ora

    Department of Physics, Budapest University of Technology and Economics, Budafoki \'ut 8, 1111 Budapest, Hungary

  • Ferenc Simon

    Budapest University of Technology and Economics, Department of Physics, Budapest University of Technology and Economics, Budafoki \'ut 8, 1111 Budapest, Hungary

  • Roderich Moessner

    Max Planck Institut f\"ur komplexe Systeme, N\"othnitzer Stra\ss e 38, D-01187 Dresden, Germany, Max-Planck-Institut f\"ur Physik komplexer Systeme, N\"othnitzer Str. 38, 01187 Dresden, Germany, MPI-PKS Dresden, Max-Planck-Institute for the Physics of Complex Systems, Max Planck Institute for the Physics of Complex Systems, MPI-PkS, Dresden, Germany