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arXiv · 2108.04248

Capacitively-coupled and inductively-coupled excitons in bilayer MoS$_2$

Lukas Sponfeldner·Nadine Leisgang·Shivangi Shree·Ioannis Paradisanos·Kenji Watanabe·Takashi Taniguchi·Cedric Robert·Delphine Lagarde·Andrea Balocchi·Xavier Marie·Iann C. Gerber·Bernhard Urbaszek·Richard J. Warburton
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Abstract

The interaction of intralayer and interlayer excitons is studied in a two-dimensional semiconductor, homobilayer MoS$_2$. It is shown that the measured optical susceptibility reveals both the magnitude and the sign of the coupling constants. The interlayer exciton interacts capacitively with the intralayer B-exciton (positive coupling constant) consistent with hole tunnelling from one monolayer to the other. Conversely, the interlayer exciton interacts inductively with the intralayer A-exciton (negative coupling constant). First-principles many-body calculations show that this coupling arises via an intravalley exchange-interaction of A- and B-excitons.

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Lukas Sponfeldner, Nadine Leisgang, Shivangi Shree, Ioannis Paradisanos, Kenji Watanabe, Takashi Taniguchi, Cedric Robert, Delphine Lagarde, Andrea Balocchi, Xavier Marie, Iann C. Gerber, Bernhard Urbaszek, Richard J. Warburton. 2021-08-09. Capacitively-coupled and inductively-coupled excitons in bilayer MoS$_2$. https://doi.org/10.1103/physrevlett.129.107401

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