Improvement of the spectra signal-to-noise ratio of caesium 6P3/2–8S1/2 transition and its application in laser frequency stabilization

Abstract

The spectra of the 133Cs 6P3/2–8S1/2 transition have been demonstrated by using both the double resonance optical pumping (DROP) and the optical–optical double resonance (OODR) techniques. Compared with the OODR technique, the DROP spectra show a much better signal-to-noise ratio and narrow spectral linewidth. When the frequency of a 795 nm external-cavity diode laser is stabilized to the DROP spectrum of 133Cs 6P3/2 F′ = 5–8S1/2 F″ = 4 transition, the lowest square root of the Allan variance of 4.1 × 10−12 at an averaging time of 100 s was obtained.