FREQUENCY-STABILIZED DIODE-LASER WITH THE ZEEMAN SHIFT IN AN ATOMIC VAPOR

We demonstrate a robust method of stabilizing a diode laser frequency to an atomic transition. This technique employs the Zeeman shift to ge nerate an antisymmetric signal about a Doppler-broadened atomic resona nce, and therefore offers a large recapture range as well as high stab ility. The frequency of a 780-nm diode laser. stabilized to such a sig nal. in Rb, drifted less than 0.5 MHz peak-peak (1 part in 10(9)) in 3 8 h. This tunable frequency lock can he constructed inexpensively, req uires little laser power, rarely loses lock, and can be extended to ot her wavelengths by use of different atomic species. (C) 1998 Optical S ociety of America.