Modulation transfer spectroscopy on Cs D2 line exposed to a dual-frequency laser field

Modulation transfer spectroscopy is a pump-probe technique which can generate dispersive-like lineshapes suitable for laser frequency stabilization. In this study, a new type of modulation transfer spectroscopy is accomplished by utilizing a dual-frequency laser system. The dual frequency laser is obtained using an acousto-optic modulator (AOM). We identified and characterized modulation transfer spectroscopy on the D2 transitions in Cs using an electro-optic modulator (EOM). We show that the amplitude of modulation transfer spectroscopy signals, for the Cs F=4 Ĭ F’=5 and the crossover resonance induced by the dual frequency laser, can be significantly enhanced by addressing more nonzero-velocity groups. The new modulation transfer spectroscopy signal with higher the peak to peak amplitude than original modulation transfer spectroscopy signal is observed. The modulation transfer signal for the crossover resonance induced by the dual frequency laser is also can generate a clear line for laser frequency stabilization, and may be helpful to improve the frequency stability. © 2021 SPIE.