Polarization Steering Light Beam Shifts via a High-Efficiency Photonic Crystal Slab

The manipulation of light fields using micro/nano photonic structures has become a pivotal area in modern optics, enabling precise control over light propagation and interaction at subwavelength scales. This study demonstrates a high-efficiency method for steering light beam displacement at optical interfaces through polarization control using a reflective photonic crystal (PhC) slab. The reflective PhC slab enhances cross-polarization efficiency by reducing scattering channels, facilitating clear observation of beam shifts without the need for additional polarization analysis. By varying the polarization state of incident light, continuous magnitude and direction control over the beam shift at the PhC slab are achieved. In practical experiments, a maximum cross-polarized efficiency over 74 (Formula presented.) and the tunable displacement range reaching up to 14 wavelengths at 780 nm are realized. This work proposes an effective approach to realizing controllable beam displacement, while also inspiring future developments in precise and efficient beam steering through photonic band and polarization engineering.