“…Strong coupling effects have been widely demonstrated in conventional semiconductor materials such as GaAs quantum dots, GaN and ZnO wide-bandgap semiconductors, and organic polymer materials. ,, However, under ambient conditions, the realization of strong coupling in these materials is challenging due to either exciton bleaching, the limited thermal stability of excitons or the strong localization effect of disordered potentials. ,,, The recent discovery of two-dimensional transition metal dichalcogenides (TMDCs) has opened new opportunities for addressing these downsides owing to their remarkable optical properties such as high excitation binding energy of approximately 100 meV, easy observation of excitonic effects at room temperatures, fixed vacuum field, and the presence of neutral and charge exciton resonances in the material. ,,,,,− The large transition dipole moments, direct bandgaps, high absorptivity, and narrow line widths are other advantages that make the monolayers of these TMDCs materials as ideal platforms for the realization of the exciton–polaritons. ,, Moreover, the locked spin and valley degrees of freedom of the monolayer TMDCs materials provide new opportunities for exploring valley polaritons and exhibit great potential for novel device architectures. ,,, Recently, the TMDCs excitons have been utilized to develop polaritons at room temperature through strong coupling between TMDCs and the various systems including distributed Bragg reflectors (DBRs), and vertical Fabry–Perot (FP) cavities. ,,,, However, such systems suffer from several drawbacks which adversely affect the field of exciton–polaritonics such as complicated fabrication processes, difficulty to engineer the mode or dispersion of the cavity, relatively rigid and bulky against postprocessing. , Hence, the investigation of new photonic structures to achieve strong coupling in the TMDCs materials is still necessary to facilitate the development of polariton-based devices. ,,, …”