We demonstrate a robust method for frequency stabilization of a diode laser by two Doppler-broadened absorption spectra of the cesium <i>D</i>2 line. This technique employs an acousto-optical modulator to generate another frequency component from a diode laser to perform the spectroscopy. The 852-nm diode laser with frequency stabilization at the zero crossing of the error signal showed a peak-to-peak fluctuation of 800 kHz compared with a frequency-stabilized femtosecond laser over a 2-h period. This frequency-locking method is free of modulation and can be applied to frequency discriminators as well as to atomic resonances.
© 2004 Optical Society of America
Jin-Long Peng and Hyeyoung Ahn, "Diode-Laser Frequency Stabilization by Two-Frequency Doppler-Broadened Absorption Spectroscopy," Appl. Opt. 43, 5860-5863 (2004)