Observation and characterization of oscillating Turing rolls and intermittency in Kerr microresonators

We report the experimental observation of Oscillating Turing Rolls (OTRs)—a new exact periodic solution of the Lugiato–Lefever equation (LLE)—in compact Si₃N₄ microring resonators with 23 μm radius (FSR = 1 THz) and strong dispersion (D₂/2π = 49 MHz). The small cavity size makes the spatial period comparable to the resonator length, enabling observation of pure temporal intermittency. Using optical and electrical spectrum analyzers, we capture intracavity power oscillations with 0.25 ns resolution. As pump power increases, the OTR region expands, showing switching between single- and double-period oscillations for different detunings, followed by a chaotic modulation-instability regime. We further observe intermittency, characterized by periodic switching between regular and chaotic dynamics over microsecond-to-second timescales, marking the transition to fully developed optical chaos.