Optica publication: 36 Hz integral linewidth laser based on a photonic integrated 4.0 m coil resonator

Our coil resonator results are published in Optica

July 7, 2022

We report a significant advance in integrated laser linewidth narrowing, stabilization, and noise reduction by use of a photonic integrated 4.0 m long coil resonator to stabilize a semiconductor laser. We achieve a 36 Hz 1/π-integral linewidth, Allan deviation of 1.8e-13 at 10 ms measurement time, and a 2.3 kHz/s drift—to the best of our knowledge, the lowest integral linewidth and highest stability demonstrated for an integrated waveguide reference cavity.