Dynamics of a ring resonator under simultaneous index and loss modulation

TL;DR

This paper provides an exact steady-state solution for a ring resonator modulated simultaneously in index and loss, enabling better modeling and novel frequency conversion capabilities.

Contribution

It offers the first complete solution for combined index and loss modulation in ring resonators, advancing understanding of their dynamics and applications.

Findings

Exact steady-state solution for combined modulation

Optimal parameters for microwave-to-optical conversion

Demonstration of selective downward frequency conversion

Abstract

We report a complete steady-state solution to the time rate equations governing the dynamics of a sinusoidally driven ring modulator. Compared to previous works that provide comprehensive solutions for pure index (phase) or loss (loss) modulation, this work presents an exact solution with their simultaneous modulation. Furthermore, the optimum modulation parameters for efficient microwave-to-optical conversion are discussed under such concurrent modulation. As an application, we report selective downward frequency conversion from the ring modulator which is not possible from pure loss or index modulation. The work allows for more accurate modeling of the ring modulator. It provides an insight to explore the interplay between phase and amplitude modulation in MRMs for unique applications, and fully understand the limitations of such devices.