Fig. 5: Octave spanning zero-dispersion soliton spectrum, MR1.

a Experimental measurement of the resonator integrated dispersion D_int, along with the spectrally extended fitted solution, and solution shifted by + D₁. Pump frequency (and pump detuning) marked by the vertical red line (horizontal dashed line). Phase-matched locations of dispersive waves marked by circles, with momentum mismatch in dotted red arrow. b Measured spectrum of ZDS⁽⁴⁾, with dispersive waves marked with arrows corresponding to the circles in a. Insets show individual comb lines. The left-most trace is in gray to indicate it is the second-order diffraction spectrum of DW2, and not genuine. c Frequency domain and d time domain simulation of ZDS⁽⁴⁾ with dispersive-wave tails marked. The close agreement of the central spectral fringes between the experiment and simulation gives us confidence that we are observing a four-peak, 80 fs pulse (showed in linear scale inset).