Gradient magnifier lens with homogeneous isotropic dielectrics for subwavelength super-imaging

A general method is proposed to design gradient magnifier lens for far-field optical subwavelength imaging. Different from previous superlens and hyperlens created by metamaterial, this magnifier lens is made of isotropic dielectric materials with gradient refractive index. More importantly, the profile of gradient refractive index can be arbitrary, which gives us a huge degree of flexibility and freedom in fabrication. Since the lens is isotropic, we can use grey-scale lithography to adiabatically tailor the topology of a dielectric layer adjacent to a metal surface. This work may have potential application in perfect lens to create sub-diffraction resolution.