A mixed-field formulation for modeling dielectric ring resonators and its application in optical frequency comb...

Area of Science:

• Photonics and Optical Engineering
• Computational Electromagnetics
• Materials Science

Background:

• Dielectric ring resonators are crucial for optical frequency comb (OFC) generation.
• Accurate modal analysis is essential for optimizing OFC device performance.
• Existing methods often struggle with spurious modes and boundary conditions.

Purpose of the Study:

• To introduce a novel finite-difference frequency-domain (FDFD) method for modal analysis of dielectric ring resonators.
• To improve accuracy and efficiency in simulating these critical OFC components.
• To streamline the dispersion engineering process for OFC design.

Main Methods:

• A new FDFD formulation solving for coupled electric and magnetic fields simultaneously.
• Utilizes cylindrical coordinates for enhanced accuracy at material boundaries.
• Automates azimuthal mode number identification, eliminating manual input.

Main Results:

• The solver accurately predicts effective indices, integrated dispersion, and resonance linewidths.
• Demonstrated excellent agreement with experimental data and commercial solvers.
• Successfully validated for silicon nitride resonators at 1060 nm and 1550 nm.

Conclusions:

• The developed FDFD solver offers a robust and efficient tool for dielectric ring resonator analysis.
• Enables accurate prediction of anomalous dispersion and coupling dynamics.
• Facilitates the design of high-performance microresonator-based OFC devices.