An EPFL team has developed a chip-integrated laser that keeps a highly stable frequency across the whole range tested, without needing active electronic control to continuously correct its operation.
In tests, the system cut frequency noise by more than 5,000 times and kept a linewidth below 10 hertz. The technology could pave the way for compact, low-noise lasers for atomic clocks, quantum sensors, communications, LiDAR and optical sensing.


