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arXiv · 1901.08500

Controlling excitons in an atomically thin membrane with a mirror

You Zhou·Giovanni Scuri·Jiho Sung·Ryan J. Gelly·Dominik S. Wild·Kristiaan De Greve·Andrew Y. Joe·Takashi Taniguchi·Kenji Watanabe·Philip Kim·Mikhail D. Lukin·Hongkun Park
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Abstract

We demonstrate a new approach for dynamically manipulating the optical response of an atomically thin semiconductor, a monolayer of MoSe2, by suspending it over a metallic mirror. First, we show that suspended van der Waals heterostructures incorporating a MoSe2 monolayer host spatially homogeneous, lifetime-broadened excitons. Then, we interface this nearly ideal excitonic system with a metallic mirror and demonstrate control over the exciton-photon coupling. Specifically, by electromechanically changing the distance between the heterostructure and the mirror, thereby changing the local photonic density of states in a controllable and reversible fashion, we show that both the absorption and emission properties of the excitons can be dynamically modulated. This electromechanical control over exciton dynamics in a mechanically flexible, atomically thin semiconductor opens up new avenues in cavity quantum optomechanics, nonlinear quantum optics, and topological photonics.

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You Zhou, Giovanni Scuri, Jiho Sung, Ryan J. Gelly, Dominik S. Wild, Kristiaan De Greve, Andrew Y. Joe, Takashi Taniguchi, Kenji Watanabe, Philip Kim, Mikhail D. Lukin, Hongkun Park. 2019-12-01. Controlling excitons in an atomically thin membrane with a mirror. https://doi.org/10.1103/physrevlett.124.027401

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