Realizing sub-wavelength imaging with evolutionary optimization

Here we propose an approach to realize farfield subwavelength imaging lens by combining the transformation optics methodology with evolutionary optimization method. The lens is composed of an isotropic dielectric core and anisotropic or isotropic dielectric matching layer, of which the parameters are obtained by applying the evolutionary optimization inverse design. Compared to previous approaches based on the simple discretized approximation of a coordinate transformation design, our method allows for much more precise recovery of the information of objects, especially for those with asymmetric shapes.