Fabrication of high-quality PMMA/SiO_<i>x</i> spaced planar microcavities for strong coupling of light with monolayer WS₂ excitons

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 polariton condensation superfluidity at room temperature. However, integrating monolayer TMDCs into high-quality planar microcavities achieve the required strong coupling between cavity photons TMDC excitons (bound electron–hole pairs) has proven challenging. Previous approaches integration had compromise various adverse effects on strength of light–matter interactions monolayer, photon lifetime, lateral size microcavity. Here, we demonstrate scalable approach fabricate with an integrated WS 2 layer-by-layer by using polymethyl methacrylate/silicon oxide (PMMA/SiO x ) spacer. Because exciton oscillator is well protected against processing steps PMMA layer, investigated this work, which quality factors above 10 3 , can operate regime This important step toward fabricating wafer-scale patterned for engineering exciton-polariton potential landscape, essential enabling many proposed technologies.