Fig. 1. Schematic illustration of the structure under study. Two CW pumps are amplified by an erbium-doped fiber amplifier (EDFA) and filtered by a bandpass filter (BPF) separately, then combined by a coupler with a ratio α1. The combined pumps are coherently added to the lightwave circulating in the resonator through a coupler with a power transmission coefficient θ. After filtering the pump frequency using a fiber Bragg grating (FBG), the generated spectrum is detected by an optical spectrum analyzer (OSA).

Fig. 2. Spectrum of the dual-pump field in the second step.

Fig. 3. (a), (b), and (c) show the evolution of the intracavity power and spectral and temporal profiles when scanning a laser over a monolithic Si3N4 ring resonator, respectively, with a 200 μm diameter and a quality factor Q=3×105. FSR=226  GHz; β2=−4.711×10−26  s2 m−1; γ=1  W−1 m−1; α=θ=0.009; Pin1=0.755  W; δ0=−0.0045; L=628  μm; and the tuning speed is 4×10−3  ns−1.

Fig. 4. Same as Fig. 3 but with a slower tuning speed of 8×10−4  ns−1.

Fig. 5. (a) and (b) correspond to the temporal profile (left) and spectrum (right) of the intracavity field when pumped with a single CW pump at the end of the first step at simulation time t=50  ns, and with da ual pump in the second step at a simulation time t=625  ns, respectively. The width of the temporal window is equivalent to the round-trip time of the field.

Fig. 6. Shows the route to the steady-state soliton of LLE. The left panel demonstrates the temporal evolution of intracavity field, where τ and t are the fast time and slow time, respectively. t≤50  ns corresponds to the first step with a single pump. The right panel shows the frequency spectrum evolution.

Fig. 7. (a) and (b) show the temporal profile and spectrum of the relationship between the steady-state solution in the second step and the total simulation time in the first step, respectively. (c) and (d) show the temporal profile and spectrum of a possible steady-state solution in the second step. (e) and (f) show the temporal profile and spectrum of another possible steady-state solution in the second step.

Fig. 8. Generated multi-FSR mode spacing solitons following the same steps and with the same resonator parameters used in Fig. 3. (a), (b), and (c) correspond to fm=2FSR, 3FSR, and 4FSR. The pictures on the left are the temporal profiles. The pictures on the right show the corresponding spectra.