Fig. 1: Pumping strategies of soliton microcombs.
From: Power-efficient ultra-broadband soliton microcombs in resonantly-coupled microresonators
a, c Left: configurations of a nonlinear microresonator pumped via a waveguide coupler (a) or a resonant coupler (c), with the optical power indicated by color. Right: corresponding diagrams of energy flow. b The “impossible trinity” of soliton microcombs under limited pump power. d Top: effective pump power versus detuning. The dashed grey line denotes the minimum pump power required for soliton microcombs. Red and blue dots indicate the maximum detuning for soliton microcombs generated using waveguide couplers and resonant couplers, respectively. Bottom: optical spectra for soliton microcombs at the two detunings, obtained using waveguide couplers (red) and resonant couplers (blue)
