Design of a resonator-bus-resonator anti-parity-time-symmetric integrated optical gyroscope

Integrated optical gyroscopes are urgently required in different fields where space occupation and weight need to be minimized. However, in the state-of-the-art ring-based optical gyroscopes, Sagnac resonance splitting is proportional to the radius of the resonator, making it impossible to design an integrated gyroscope for high-resolution requirements. The enhancement of the sensitivity and the improvement in the limit of detection enabled by exceptional points has been already experimentally proved for parity-time-symmetric gyroscopes. Anti-parity-time-symmetric gyroscopes have been demonstrated to show even better performance, exhibiting a real eigenfrequency splitting, that can be easily measured. Here we present, for the first time, a resonator-bus-resonator anti-parity-time-symmetric integrated optical gyroscope designed on InP platform. This completely new architecture critically reduces the fabrication tolerance problems. The proposed configuration makes the gyroscope robust against the external perturbations that would make previous designs exit from the anti-PT-symmetric condition. Moreover, this new architecture enables an electrical fine-tuning method for setting the system at the exceptional point. Finally, a time domain analysis is performed in this work, using the Fast Fourier Transform, to demonstrate the ease of its readout.