Collective modes of twisted van der Waals materials

 · Invited

Abstract

Rotationally misalignment profoundly modifies electronic and lattice properties of van der Waals materials. If the twist angle between adjacent layers is small, a periodic network of dislocations (solitons) delineating large commensurate domains appears. The solitons can have a strong influence on collective modes of the system. A twisted bilayer graphene can act as a photonic crystal for two-dimensional plasmon modes. Propagation of plasmons along one-dimensional links and their scattering at the nodes of the network produces multi-band plasmonic spectra quasiperiodic in frequency. In a twisted boron nitride, the solitons can induce shift and splitting of phonon-polaritons. Our theory and modeling provides explanation for recent nano-optical experiments with twisted van der Waals heterostructures and indicates some possible future directions in this field.

*Our work is supported by the Office of Naval Research.

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Presenters

  • Michael Fogler

    • University of California, San Diego
    • Department of Physics, University of California San Diego
    • UC San Diego
    • Department of Physics, University of California, San Diego
    • UCSD
    • University of California San Diego

Authors

  • Michael Fogler

    • University of California, San Diego
    • Department of Physics, University of California San Diego
    • UC San Diego
    • Department of Physics, University of California, San Diego
    • UCSD
    • University of California San Diego