Microscopic theory of exciton and trion polaritons in doped monolayers of transition metal dichalcogenides

This is the final version. Available on open access from Nature Research via the DOI in this recordData availability: The data that support the findings of this study are available from the corresponding author upon reasonable request.Code availability: All the codes were implemented using home-built programs, which use standard open-source software packages.We study a doped transition metal dichalcogenide (TMDC) monolayer in an optical microcavity. Using the microscopic theory, we simulate spectra of quasiparticles emerging due to the interaction of material excitations and a high-finesse optical mode, providing a comprehensive analysis of optical spectra as a function of Fermi energy and predicting several modes in the strong light-matter coupling regime. In addition to exciton-polaritons and trion-polaritons, we report polaritonic modes that become bright due to the interaction of excitons with free carriers. At large doping, we reveal strongly coupled modes corresponding to excited trions that hybridize with a cavity mode. We also demonstrate that the increase of carrier concentration can change the nature of the system’s ground state from the dark to the bright one. Our results offer a unified description of polaritonic modes in a wide range of free electron densities.Deutsche Forschungsgemeinschaft (DFG)Russian Science FoundationIcelandic Research FundRussian Foundation for Basic Research (RFBR)Engineering and Physical Sciences Research Council (EPSRC)University at BuffaloSUNY Research Seed Grant Progra