Electrostatic Traps of Interlayer Excitons in MoSe2/WSe2 Heterostructures

ORAL

Abstract

The two-dimensional (2D) nature and large excitonic binding energy of transition metal dichalcogenides (TMDs) allow for the exploration of novel quantum optical effects. Using type-II heterostructures formed by stacking MoSe2 and WSe2 monolayers, optical excitation generates interlayer excitons, bound electrons and holes residing in spatially separated layers. The out-of-plane, permanent dipole moment of interlayer excitons allows for the control of the emission energy by tuning the vertical electric field using dual-gated devices. By spatially varying the vertical electric field with patterned gates, we can generate potential profiles that can spatially control the interlayer exciton energy. We observe changes in the exciton cloud shape and emission brightness depending on a flat, trapping, or anti-trapping electric field profile. Finally, we estimate an upper-bound interlayer exciton density that can be tuned with the trap depth. With the ability to generate high densities of interlayer excitons, trapped interlayer excitons can serve as a platform for generating and exploring Bose-Einstein condensates at high temperatures.

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Presenters

  • Andrew Joe

    Harvard University

Authors

  • Andrew Joe

    Harvard University

  • Luis Jauregui

    Physics, Harvard University, Harvard University

  • Kateryna Pistunova

    Physics, Harvard University, Harvard University

  • You Zhou

    Chemistry and Chemical Biology, Harvard University, Harvard University

  • Kristiaan De Greve

    Harvard University, Physics, Harvard University

  • Andrey Sushko

    Physics, Harvard University, Harvard University

  • Giovanni Scuri

    Physics, Harvard University, Harvard University

  • Mikhail Lukin

    Harvard University, Physics, Harvard University

  • Hongkun Park

    Dept. of Chemistry and Chemical Biology and Dept. of Physics, Harvard University, Harvard University, Chemistry and Chemical Biology, Harvard University

  • Philip Kim

    Harvard University, Department of Physics, Harvard University & School of Engineering and Applied Sciences, Harvard University, Department of Physics, Harvard University, Cambridge, MA 02138, USA., Physics, Harvard University, Physics and Applied Physics, Harvard University, Physics department, Harvard University