STABILIZED DIODE-LASER SYSTEM WITH GRATING FEEDBACK AND FREQUENCY-OFFSET LOCKING

Reported is a diode-laser system that utilizes optical feedback from a diffraction grating to stabilize the diode-laser frequency and to red uce the linewidth. Electronic control is also incorporated to compensa te for mechanical and thermal noise. The resultant system can be tuned +/-5 nm from the free-running laser wavelength, can be continuously s canned up to 10 GHz, and has a linewidth of approximately 150 kHz as d etermined by observing the heterodyne beat note between two systems. R esults are also presented of frequency-offset locking of two lasers us ing a simple electronic frequency discriminator that relies on a digit al delay generator. The frequency difference between two lasers can be continuously tuned from 2 to 30 MHz.