Turing pattern frequency combs in microring resonators with quadratic nonlinearity

: (Alternative Format Thesis)

Abstract

This thesis develops models and computational techniques for understanding Turingpattern frequency comb generation in high-Q microring resonators with quadratic non-linearity. Coupled mode equations describe nonlinear modal interactions via phase-matched intermodal coupling. Efficient numerical methods simulate the multimodedynamics and stability calculations predict parametric instability thresholds.These techniques are applied to demonstrate Turing pattern combs emerging from cas-caded four-wave mixing and instability enabled by 𝜒(2) intermodal coupling, withoutsoliton pulse shaping. A dressed state analysis provides insight into the interplay be-tween quadratic nonlinearity, phase matching, and walk-off underlying comb formation.Complex dynamics are shown to transition to mode-locked Turing pattern states.Near phase-matching induces Eckhaus instabilities and multimode chaos. Unusualtwo-color cavity solitons are predicted outside single-mode bistability. The models andsimulations provide new physical understanding of Turing pattern formation, stability,and dynamics in 𝜒(2) microrings. This establishes an integrated platform for generatingnovel on-chip Turing pattern frequency comb sources.

Date of Award	11 Sept 2024
Original language	English
Awarding Institution	University of Bath
Supervisor	Dmitry Skryabin (Supervisor) & Andriy Gorbach (Supervisor)