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arXiv · 2103.01731

Out-of-plane emission of trions in monolayer WSe2 revealed by whispering gallery modes of dielectric microresonators

D. Andres-Penares·M. K. Habil·A. Molina-Sánchez·C. J. Zapata-Rodríguez·J. P. Martínez-Pastor·J. F. Sánchez-Royo
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Abstract

The manipulation of light emitted by two-dimensional semiconductors grounds forthcoming technologies in the field of on-chip communications. However, these technologies require from the so elusive out-of-plane photon sources to achieve an efficient coupling of radiated light into planar devices. Here we propose a versatile spectroscopic method that enables the identification of the out-of-plane component of dipoles. The method is based on the selective coupling of light emitted by in-plane and out-of-plane dipoles to the whispering gallery modes of spherical dielectric microresonators, in close contact to them. We have applied this method to demonstrate the existence of dipoles with an out-of-plane orientation in monolayer WSe2 at room temperature. Micro-photoluminescent measurements, numerical simulations based on finite element methods, and ab-initio calculations have identified trions as the source responsible for this out-of-plane emission, opening new routes for realizing on-chip integrated systems with applications in information processing and quantum communications.

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D. Andres-Penares, M. K. Habil, A. Molina-Sánchez, C. J. Zapata-Rodríguez, J. P. Martínez-Pastor, J. F. Sánchez-Royo. 2021-03-02. Out-of-plane emission of trions in monolayer WSe2 revealed by whispering gallery modes of dielectric microresonators. https://arxiv.org/abs/2103.01731

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