We demonstrate the generation of frequency combs with a low repetition rate of 450 MHz, using a hybrid integrated InP-Si3N4 diode laser with more than 60 cm optical roundtrip length on-chip. Comb generation is achieved without a saturable absorber, based on four-wave mixing in combination with gain-index coupling and spectrally filtered feedback; both passive and active mode-locking is observed. External modulation reduces the RF linewidth from several hundreds of kHz to the ten-kHz level.
|Publication status||Published - 17 Sep 2022|
|Event||European Semiconductor Laser Workshop 2022 - Neuchatel, Switzerland|
Duration: 16 Sep 2022 → 17 Sep 2022
|Conference||European Semiconductor Laser Workshop 2022|
|Period||16/09/22 → 17/09/22|