Polarization-independent Imaging With Annular Photonic Crystal Slab

摘要

The imaging behaviors for both polarizations of electromagnetic wave in two-dimensional annular photonic crystal flat lens are theoretical investigated. For the TE-polarization, the subwavelength imaging induced by negative refraction is obtained. In contras',for the TM-polarization, the realting optical field distribution behind the slab resembles a triple point source due to the effect of channeling, the light can focus again by the interference effect. Especially, the image of unpolarized wave point source can be realized and image distance can be reduced as the source-slab distance increasing. These results show that the negative refraction is not the one and only mechanism of imaging by PC slab.