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arXiv · 1712.04485

Observation of Inter-layer Excitons in MoSe2 Single Crystals

Jason Horng·Tineke Stroucken·Long Zhang·Eunice Y. Paik·Hui Deng·Stephan W. Koch
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Abstract

Interlayer excitons are observed coexisting with intralayer excitons in bi-layer, few-layer, and bulk MoSe2 single crystals by confocal reflection contrast spectroscopy. Quantitative analysis using the Dirac-Bloch-Equations provides unambiguous state assignment of all the measured resonances. The interlayer excitons in bilayer MoSe2 have a large binding energy of 153 meV, narrow linewidth of 20 meV, and their spectral weight is comparable to the commonly studied higher-order intralayer excitons. At the same time, the interlayer excitons are characterized by distinct transition energies and permanent dipole moments providing a promising high temperature and optically accessible platform for dipolar exciton physics.

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Jason Horng, Tineke Stroucken, Long Zhang, Eunice Y. Paik, Hui Deng, Stephan W. Koch. 2017-12-12. Observation of Inter-layer Excitons in MoSe2 Single Crystals. https://doi.org/10.1103/physrevb.97.241404

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