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arXiv · 2302.10312

Extended spatial coherence of interlayer excitons in MoSe$_2$/WSe$_2$ heterobilayers

Mirco Troue·Johannes Figueiredo·Lukas Sigl·Christos Paspalides·Manuel Katzer·Takashi Taniguchi·Kenji Watanabe·Malte Selig·Andreas Knorr·Ursula Wurstbauer·Alexander W. Holleitner
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Abstract

We report on the spatial coherence of interlayer exciton ensembles as formed in MoSe$_2$/WSe$_2$ heterostructures and characterized by point-inversion Michelson-Morley interferometry. Below 10 K, the measured spatial coherence length of the interlayer excitons reaches values equivalent to the lateral expansion of the exciton ensembles. In this regime, the light emission of the excitons turns out to be homogeneously broadened in energy with a high temporal coherence. At higher temperatures, both the spatial coherence length and the temporal coherence time decrease, most likely because of thermal processes. The presented findings point towards a spatially extended, coherent many-body state of interlayer excitons at low temperature.

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Mirco Troue, Johannes Figueiredo, Lukas Sigl, Christos Paspalides, Manuel Katzer, Takashi Taniguchi, Kenji Watanabe, Malte Selig, Andreas Knorr, Ursula Wurstbauer, Alexander W. Holleitner. 2023-02-20. Extended spatial coherence of interlayer excitons in MoSe$_2$/WSe$_2$ heterobilayers. https://doi.org/10.1103/physrevlett.131.036902

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