Abstract We report a monolithically integrated coupled extended-cavity distributed Bragg reflector laser with, to our knowledge, the lowest reported intrinsic linewidth of ∼10 kHz, which is extracted from a corresponding frequency-noise level of ∼3200 Hz2/Hz, realized on an InP generic foundry platform. Using the delayed self-heterodyne method, the experimentally measured linewidth was 45 kHz. The laser has an on-chip optical output power of 18 mW around 1550 nm at an injection current of 95 mA.
