On-Chip Tunable MZI Reference Cavity for 1550 nm Laser Stabilization

Low-noise stabilized lasers have widespread applications in fields such as precision measurement, atomic physics, quantum computing, and microwave photonics.We have proposed an on-chip Mach-Zehnder Interferometer (MZI) frequency reference source, which uses Pound-Drever-Hall (PDH) stabilization technology to lock a semiconductor laser to the MZI chip. After locking, the frequency noise is suppressed by up to 24 dB. The relative stability of the Distributed Feedback (DFB) laser after locking reaches 3ⅹ10-10 at 10 ms, an improvement of an order of magnitude compared to free-running operation. The linewidth of the stabilized laser is 510 kHz at an integration time of 100 ms, narrowed by 20 times compared to the free-running state.