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arXiv · 1905.12296

Electrically tuneable exciton energy exchange between spatially separated 2-dimensional semiconductors in a microcavity

Henry A. Fernandez·Freddie Withers·Saverio Russo·William L. Barnes
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Abstract

Electrical control over the energy exchange between exciton states mediated by cavity-polaritons at room temperature is demonstrated. Spatially separated field effect transistors based on monolayers of WS$_2$ and MoS$_2$ are placed in a tuneable Fabry-Pérot microcavity. This device is specially designed for the formation of exciton-polaritons that combine the two exciton species and a tuneable cavity mode. It is further shown that the tuning of the free carrier density in the WS$_2$ film leads to a strong modulation of the Rabi splitting that modifies the excitonic and photonic nature of exciton-polaritons. Electrical control of polaritonic devices may lead to technological applications using switchable quantum states.

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Henry A. Fernandez, Freddie Withers, Saverio Russo, William L. Barnes. 2019-05-29. Electrically tuneable exciton energy exchange between spatially separated 2-dimensional semiconductors in a microcavity. https://doi.org/10.1063/1.5110492

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