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arXiv · 1710.04294

Excitonic emission of monolayer semiconductors near-field coupled to high-Q microresonators

Clément Javerzac-Galy·Anshuman Kumar·Ryan D. Schilling·Nicolas Piro·Sina Khorasani·Matteo Barbone·Ilya Goykhman·Jacob B. Khurgin·Andrea C. Ferrari·Tobias J. Kippenberg
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Abstract

We present quantum yield measurements of single layer $\textrm{WSe}_2$ (1L-$\textrm{WSe}_2$) integrated with high-Q ($Q>10^6$) optical microdisk cavities, using an efficient ($\eta>$90%) near-field coupling scheme based on a tapered optical fiber. Coupling of the excitonic emission is achieved by placing 1L-WSe$_2$ to the evanescent cavity field. This preserves the microresonator high intrinsic quality factor ($Q>10^6$) below the bandgap of 1L-WSe$_2$. The nonlinear excitation power dependence of the cavity quantum yield is in agreement with an exciton-exciton annihilation model. The cavity quantum yield is $\textrm{QY}_\textrm{c}\sim10^{-3}$, consistent with operation in the \textit{broad emitter} regime (i.e. the emission lifetime of 1L-WSe$_2$ is significantly shorter than the bare cavity decay time). This scheme can serve as a precise measurement tool for the excitonic emission of layered materials into cavity modes, for both in plane and out of plane excitation.

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Clément Javerzac-Galy, Anshuman Kumar, Ryan D. Schilling, Nicolas Piro, Sina Khorasani, Matteo Barbone, Ilya Goykhman, Jacob B. Khurgin, Andrea C. Ferrari, Tobias J. Kippenberg. 2017-10-11. Excitonic emission of monolayer semiconductors near-field coupled to high-Q microresonators. https://doi.org/10.1021/acs.nanolett.8b00749

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