A fresh look at interlayer emission from WSe2/MoS2 heterostructures

ORAL

Abstract

The recent two years have seen a rising interest in the study of interlayer excitons (ILX) in Van der Waals layered materials, where electron-hole pairs are bound together across the interlayer gap. Special attention was drawn to such ILX in heterostructures of semiconductor transition metal dichalcogenides with staggered band alignment such as MoSe2 and WSe2. That includes the exploration of their optical properties, lifetime, optical selection rules, spin/valley properties, the influence of crystal alignment (a.k.a the moire pattern), the role of momentum-indirect transition, etc.. The latter subject was also studied for the ILX observed in WSe2 and MoS2 heterostructure (Kunstmann et al. Nature Physics, DOI: 10.1038/s41567-018-0123-y ,2018), where the reported ~1.6 eV emission is assigned to such indirect transition. In this talk, I will report on the observation of a different interlayer emission from the same system. Probing its response to different experimental conditions, I will discuss its properties and its origin.

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Presenters

  • Ouri Karni

    Applied Physics, Stanford University

Authors

  • Ouri Karni

    Applied Physics, Stanford University

  • Elyse Barré

    Stanford University, Applied Physics, Stanford University

  • Tony F Heinz

    Stanford University & SLAC National Accelerator Laboratory, Department of Applied Physics, Stanford University, Stanford, California, 94305 USA, Applied Physics, Stanford University, Stanford University and SLAC National Laboratory, Stanford University, Stanford University & SLAC