Fig. 2: Characterization of dark pulses in AlGaAsOI microresonators.
From: Quantum decoherence of dark pulses in optical microresonators
a Left panel: the cross-sectional view of the microresonator with core dimensions of 400 nm × 1000 nm. The profile of the fundamental TE mode is overlaid. Middle panel: photograph of the AlGaAsOI microresonator used in this study. Right panel: transmission spectrum showing the intrinsic quality factor as 1.4 million. b Typical optical spectrum of a dark pulse. Inset: electrical spectrum showing dark pulse repetition frequency. c Schematic illustration of the timing jitter measurement. The instantaneous phase of the i(j)th comb line equals Φceo + i(j)Φr, with Φceo and Φr associated with the carrier-envelope-offset frequency and repetition frequency, respectively. d Measured single-sideband (SSB) jitter spectral density of the dark pulse (blue) and simulated quantum limit (red). Contributions from the intensity (yellow) and phase (cyan) noise of the pump as well as calculated thermorefractive noise (green) are also plotted to constitute the technical noise in the measurement.
