Fabrication of high-quality PMMA/SiO${}_x$ spaced planar microcavities for strong coupling of light with monolayer WS${}_2$ excitons

Abstract

Exciton polaritons in atomically-thin transition metal dichalcogenide crystals (monolayer TMDCs) have emerged as a promising candidate to enable topological transport, ultra-efficient laser technologies, and collective quantum phenomena such as polariton condensation and superfluidity at room temperature. However, integrating monolayer TMDCs into high-quality planar microcavities to achieve the required strong coupling between the cavity photons and the TMDC excitons (bound electron-hole pairs) has proven challenging. Previous approaches to integration had to compromise between various adverse effects on the strength of light-matter interactions in the monolayer, the cavity photon lifetime, and the lateral size of the microcavity. Here, we demonstrate a scalable approach to fabricating high-quality planar microcavities with an integrated monolayer WS${}_2$ layer-by-layer by using polymethyl methacrylate/silicon oxide (PMMA/SiO${}_x$) as a cavity spacer. Because the exciton oscillator strength is well protected against the required processing steps by the PMMA layer, the microcavities investigated in this work, which have quality factors of above $10^3$, can operate in the strong light-matter coupling regime at room temperature. This is an important step towards fabricating wafer-scale and patterned microcavities for engineering the exciton-polariton potential landscape, which is essential for enabling many proposed technologies.

References in corpus (9)

• Measurement of the optical dielectric function of transition metal dichalcogenide monolayers: MoS2, MoSe2, WS2 and WSe2
• Strong light-matter coupling in two-dimensional atomic crystals
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• Observation of Superfluidity of Polaritons in Semiconductor Microcavities
• Exciton Binding Energy of Monolayer WS2
• Motional narrowing, ballistic transport, and trapping of room-temperature exciton polaritons in an atomically-thin semiconductor
• Spatial coherence of room-temperature monolayer WSe${}_2$ exciton-polaritons in a trap
• Valley polarized relaxation and upconversion luminescence from Tamm-Plasmon Trion-Polaritons with a MoSe2 monolayer
• Influence of direct deposition of dielectric materials on the optical response of monolayer WS${}_2$

Cited by in corpus (1)

• Negative-mass exciton polaritons induced by dissipative light-matter coupling in an atomically thin semiconductor