Uniform and non uniform optical leaky-wave antennas for field shaping

The concept of optical leaky wave antennas based on periodic perturbations in a dielectric waveguide has been demonstrated to provide directive radiation in far field. Moreover the radiated field from such silicon-on-insulator and CMOS compatible antenna systems can be modulated through controlling the excess carrier density in silicon inclusions, and the radiation modulation with high extinction ratios were achieved by integrating the antennas in resonator topologies. In this paper we extend this concept to optical waveguides with non uniformly distributed perturbations as a method of shaping the antenna near field. The scattering of electromagnetic waves through such perturbed waveguides can be engineered using array theory or a leaky wave model. The resonator integration and Si-based designs combined with the near-field shaping technique proposed here can lead to applications such as tunable near field detection. In this paper we present a theoretical framework as a proof of the proposed concept with a CMOS compatible optical antenna.