Sid graduated with honors earlier this may. His thesis is titled 'Low-Temperature Infrared Characterization of van der Waals materials and their Method of Fabrication'
Van der Waal materials are characterized by their strong in-plane and weak inter-layer bonding, leading to exciting new properties which are of utmost technological importance, such as in quantum computation or in advanced optical devices. hBN is a well-studied insulating material, best known for its applications in Nanophotonics and plasmonics due to its naturally hyperbolic dispersion.On the other hand, Transition Metal Dichalcogenides (TMDCs) are an emerging class of 2D materials, which are well-known for their vast potential in nanoelectronic and optoelectronic properties. ReSe2 is an interesting member of this family due to its highly anisotropic nature even in the monolayer, allowing for the coupling of excitonics modes to different polarizations of light. In this thesis, I develop methods to fabricate these materials, as well as introduce the micro-spectrometer used to characterize them. The isotopic effects on the phonon energies was studied for isotopically-pure hBN samples at different temperatures. The shift in energies was also characterized for the different isotopes as a function of temperature. In ReSe2, the polarization-dependence of the excitons was studied at different temperatures. These results have huge impact in the fields of nanophotonics and engineered infrared optical devices in the case of hBN, and in polarized light sources and polarization-dependent sensing applications for ReSe2.