A semiconductor laser with a linewidth of 7 Hz locking to a supercavity was achieved by using an optical–electrical double-feedback technique. The emitted power concentration within the stabilized field spectrum was 81%. The minimum value of the square root of the Allan variance for the frequency stability was 2.4 × 10−14 at the integration time of 70 msec.
© 1990 Optical Society of America
Original Manuscript: July 6, 1990
Manuscript Accepted: October 2, 1990
Published: December 15, 1990
Chul-Ho Shin and Motoichi Ohtsu, "Stable semiconductor laser with a 7-Hz linewidth by an optical–electrical double-feedback technique," Opt. Lett. 15, 1455-1457 (1990)