Enhanced spin Hall effect due to the redshift gaps of photonic hypercrystals.

We proposed a method for enhancing the spin Hall effect (SHE) of light in the photonic hypercrystal (PHC). PHC is a periodic structure that combines the properties of hyperbolic metamaterials (HMMs) and conventional one-dimensional-photonic crystals (1DPCs). The proposed PHC is composed of Ti3O5 and HMMs, which alternatively consist of Ag and Ti3O5. The giant ratio of reflection coefficients of TE/TM polarizations can be realized due to the redshift gaps of the PHCs, where the band edge of TE polarization shifts toward short wavelengths but the band edge of TM polarization moves toward long wavelengths. It will eventually lead to the enhancement of SHE in this PHC with the redshift gaps. The maximum transverse shift can be close to 15 µm with the optimum thickness and incident angle. The enhancing SHE provides us an opportunity to expand the corresponding applications in the field of optics.