Fine Structures in Imbert-Fedorov Shift Spectrum of Monolayer MoS₂

Imbert-Fedorov (IF) shift is a direct manifest of the photonic spin Hall effect, which reveals the interaction between light and materials and the conversion between spin angular momentum and orbital angular momentum of light. However, most beam displacement measurements are focused on the incident angle dependence, which cannot characterize the response of materials to the light. In this talk, we will introduce a new technique called the beam displacement amplification technology (BDAT), which can help us reveal the fine structures in the IF shift spectra of monolayer MoS₂. Specifically, we observed multiple peaks in the IF shift spectra of monolayer MoS₂. We attribute these peaks to the optical transition between exciton levels in the material. We then construct a theoretical model for the IF shift spectra based on the Hydrogenic model of excitons in this material. We show that our model can provide a theoretical understanding for the peaks in the IF shift spectra.