Fig. 4: Hybrid integration of diode laser and germano-silicate device.
From: Towards fibre-like loss for photonic integration from violet to near-infrared
a, Schematic of SIL of the diode laser using external ultrahigh-Q microring. b, Simulated TRN spectra. Mode areas are 28.06 μm2, 7.71 μm2 and 1.33 μm2 for Ge-silica, thin Si3N4 and thick Si3N4, respectively. c, Single sideband frequency noise of SIL laser, indicating a Hz-level fundamental linewidth (FL). Inset, the image of a 1,550-nm DFB laser and integrated Ge-silica microring (indicated in false colour). d, Narrow-linewidth lasers at red, green and violet wavelengths, realized by SIL of Fabry–Pérot (FP) diode lasers to microrings. The fundamental linewidths are 15 Hz at 632 nm, 12 Hz at 512 nm and 90 Hz at 444 nm. e, Comparison of the fundamental linewidths of integrated lasers with state-of-the-art Si3N4 platforms30,31.
