SummaryAn automatic linewidth control loop which provides stable optimum linewidth reduction and single cavity mode operation of an external cavity semiconductor laser is presented. Stable linewidth reduction from 70 MHz to below 2 MHz is obtained for a 1.3 μm BH-laser, whereas simultaneous mean frequency stabilization to within 1 kHz and linewidth reduction from 17 MHz to 1.6 MHz is demonstrated for an 830 nm CSP-laser.
The Semiconductor laser frequency stabilization is the important study topic because of its increasing popular. We introduce a simply experimental setup method of the frequency stabilization of a 780 nm diode laser by only a tiny current in the laser audio modulation, photodiode receiver, and locking the transmission peaks. Use this method, the laser can be locked to the resonance peak of the Fabry-Perot cavity. The linewidth of laser is below 400 kHz, and it runs continually above 3 hours.
Laser Spectroscopy and Frequency Stabilization of a Semiconductor Laser for a 87Rb Atomic Clock