Microwave Radiation Coupling into a WGM Resonator for a High-Photonic-Efficiency Nonlinear Receiver

In this paper, a scheme for a direct coupling of the microwave radiation into a nonlinear whispering-gallery mode (WGM) receiver is presented. This nonlinear receiver can be used for the detection of the weak radiation for radio astronomy applications at room temperature. It depends on the upconverting of the microwave signal into the optical domain through a nonlinear material. The proposed scheme is able to provide a very high theoretical photonic efficiency with an enhancement around 2-3 orders of magnitude in comparison to the state-of-the-art photonic efficiency of this concept, to the best of the authors knowledge. It consists of two main parts, a metallic ring resonator, and a Dielectric Resonator Antenna (DRA).