Thickness-Dependent Refractive Index of 1L, 2L, and 3L MoS ₂ , MoSe ₂ , WS ₂ , and WSe ₂

An interesting aspect of 2D materials is the change of their electronic structure with the reduction of thickness. Molybdenum and tungsten-based transition metal dichalcogenides form an important family of 2D materials, whose members show a thickness-dependent bandgap and strong light–matter interaction. In this work, the experimental...