Nonlinear Kerr effect aperiodic Lüneburg lens

Abstract

A subwavelength-modulated dielectric nonlinear Lu¨neburg lens is proposed and numerically verified. In the linear limit, the structure focuses a plane wave to an ideal geometrical point image. In the presence of Kerr nonlinearity, focal shift to a Gaussian beam input is compensated at a tunable intensity value. Nonlinear Lu¨neburg lens is also capable of finite conjugate imaging. A modified aperiodic Lu¨neburg is also proposed to greatly reduce the aberration caused by the Kerr effect.