Tunable In-Plane and Transverse Spin Angular Shifts in Layered Dielectric Structure

The photonic spin Hall effect (SHE) manifests itself as the spin-dependent spatial and angular shifts. There are some ways for controlling the spatial shifts, however, lacks an effective method for manipulating angular shifts. In this work, we propose a simple and effective way for manipulating the spin angular shifts in photonic SHE by considering the light beam reflected at the air-layered structure interface. We theoretically derive the general expressions of the in-plane and transverse spin angular shifts in this layered structure. It is found that the in-plane and transverse spin angular shifts can be effectively regulated by adjusting the structure parameters of layered model, including amplifying or suppressing the magnitude of the angular shifts and switching their signs. Interestingly, the in-plane angular shifts can be adjusted from spin-independent to spin-dependent or vice versa when the polarization state of the incident beam varies. Importantly, as for the incident beam with vertical polarization, a near-zero reflection angle similar to Brewster angle appears. In the vicinity of this point, the large spin angular shifts can be explored.