Excitonic Physics and Emergent Phenomena in Layered Transition Metal Dichalcogenides: Progress and Prospects.

Transition metal dichalcogenides (TMDs) are a fascinating class of layered materials, distinguished by weak interlayer van der Waals forces. Their atomically thin structure and ability to form various layered assemblies provide exceptional electronic and optical properties, positioning TMDs at the forefront of condensed matter research and next-generation technologies. The presence of strong quantum confinement and reduced dielectric screening gives rise to tightly bound excitonic quasiparticles with large binding energies, enabling their existence even at room temperature. The collective interaction of these quasiparticles with other carriers or excitations yields a rich landscape of many-body effects and emergent phenomena. In this perspective, we present a unified overview of excitonic physics and many-body interactions in layered TMDs, highlighting recent developments and open challenges. We discuss how the strong quantum confinement, spin-orbit coupling, and many-body interactions shape the electronic and optical properties of various TMDs. Finally, we discuss future opportunities for TMDs-based technologies, including superabsorption, exciton crystals, single-photon emission, coupling to ferroic and correlated degrees of freedom. This perspective connects recent advances in excitonic and many-body physics in layered TMDs, highlighting emerging opportunities for quantum, photonic, and optoelectronic technologies.