Enhanced photonic spin Hall effect of reflected light from a doubly linear gradient-refractive-index material

All-optical image edge detection based on the two-dimensional photonic spin Hall effect in anisotropic metamaterial

Optical image processing based on the photonic spin Hall effect (SHE) has been gaining significant attention as a convenient and an accurate way for image edge detection. However, the recent edge imaging techniques depending on optical differentiation is mainly achieved by modulation of one-dimensional photonic SHE. Here, we theoretically predict the two-dimensional photonic SHE in the anisotropic metamaterial, and find that its longitudinal and transverse displacements exhibit spin-dependent property at filling factors with increasing incidence angle. As the transverse and in-plane displacements induced by the photonic SHE can be controlled by the filling factor of the crystal structure, the optical axis angle, and the incident angle, this intrinsical effect can be used to realize a tunable edge imaging. Interestingly, by changing the optical axis of the anisotropic metamaterial, the in-plane displacements are equal to the transverse displacements for a certain filling factor and the corresponding incident angle. Therefore, we propose a two-dimensional image edge detection method based on the photonic SHE in anisotropic metamaterial. Further numerical results validate the theoretical proposal.

Actively manipulating the photonic spin Hall effect by bias-assisted light-induced carrier injection

In this work, we present a simple and active mechanism for manipulating the photonic spin Hall effect (SHE) of an InP-based layered structure by taking advantage of the alterable refractive index of InP via bias-assisted carrier injection. The photonic SHE of transmitted light for both H- and V-polarized beams is quite sensitive to the intensity of the bias-assisted light. The spin shift can reach its giant value under the optimal intensity of bias light, which corresponds to the proper refractive index of InP induced by the photon-induced carrier injection. Except for the modulation of the bias light intensity, there is another method to manipulate the photonic SHE by adjusting the wavelength of bias light. We found that this method of tuning the bias light wavelength is more effective for H-polarized light than for the V-polarized light.