Fig. 3: Multiplexed solitons with 2/3 octave spacing.
From: Near-visible integrated soliton microcombs with detectable repetition rates
a Illustration of soliton multiplexing on a standalone coupled racetrack device pumped at 1064 nm (TM mode) and 1560 nm (TE mode). b, c Upper panels: Simulated mode profile of the 1064 nm (1560 nm) antisymmetric TM0 (TE0) mode in the racetrack coupling section (dashed line in a). Lower panels: Transmission spectrum measurements of 1064 nm (TM) and 1560 nm (TE) mode resonances giving intrinsic Q factor (Q0) of 1064 (1560) nm of 80 million (20 million). d, e Upper panels: Integrated dispersion measurements of the coupled racetrack resonator near 1064 and 1560 nm bands. The solid curves give the design targets, and agree well with the measurements marked by dots. Lower panels: The optical spectra of the multiplexed solitons are shown in the corresponding lower panels. Insets: electrical spectra of the detected 1064 and 1560 nm soliton pulse streams. The resolution bandwidth is 1 kHz.
