Investigation of the generalized Brewster angle effect in MoS2 thin films

The growing interest in two-dimensional materials is driven by both scientific curiosity in understanding their unique properties and the technological challenge of producing large-area, low-defect monolayers and bilayers for engineering their use in several applications. In optics, comprehensive characterization across a broad spectral range under controlled polarization conditions is essential.<br/> Among low-dimensional materials, graphene is by far the most well known and widely studied. Notably, its optical anisotropy induces shifts in the pseudo-Brewster angle when deposited on dielectric substrates under specific conditions, with the direction of the shift depending primarily on the spectral range and the number of layers. Molybdenum disulfide (MoS₂) exhibits a behavior analogous to that of graphene, although its properties have been less explored. In this work, we start investigating the generalized pseudo-Brewster angle effect in commercially available MoS₂ thin films deposited on bulk SiO₂, covering a wide spectral range.<br/> Our study intends to examine how the interaction between film thickness, refractive index, interference, and light polarization collectively influences the pseudo-Brewster angle, more precisely described as the generalized Brewster angle, revealing characteristic shifts that provide deeper insights into light-matter interaction in coatings based on MoS₂. Furthermore, we propose a novel method to determine the thickness of thin films MoS₂ using reflectivity measurements, offering a rapid and non-invasive characterization technique. These findings advance the development of polarization-sensitive optical components and highlight the promising potential of MoS₂ in photonic and optoelectronic applications.