Abstract

A distorted photonic crystal (DPC) is a photonic crystal (PC) that exhibits adiabatic change (lattice distortion) in its lattice properties. We have previously reported that light (electromagnetic wave) propagations in DPCs are curved even when maintaining effective refractive index (averaged in each lattice point) by using the two-dimensional finite-difference time-domain (2D-FDTD) analysis, and have experimentally demonstrated the trajectory by using THz region [1]. Not only to distortions to lattice constant, but we also have shown the DPC based on the lattice points shape that can bend and meander the light propagation [2]. These phenomena can be explained by adiabatic variations of group velocity vectors along the direction of distortion as results of the anisotropic refractive indices induced by lattice distortion. Since no spatial varies of refractive index, these light propagation controls using lattice distortion will be new approach in the fields of transformation optics. So far, we have studied the lattice distortions in which the direction of distortion and dependence of lattice distortion are the identical (e.g., the distortion in the y-direction varies in proportion to y²). In this study, we analyze light propagation in a DPC in which the direction of distortion and dependence of lattice distortion are different.

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