Sub-Doppler DAVLL for D lines of Rb atoms

A theoretical and experimental study of lineshapes in sub-Doppler DAVLL (dichroic atomic vapor laser lock) spectroscopy for the D lines of Rb atoms was presented. From the calculation of sub-Doppler DAVLL spectra using both density matrix equations and rate equations we found that the coherence effect depended significantly on the branching ratios of the transition lines. We also investigated the dependence of the amplitude and the slope of the spectra on the magnetic field and the pump beam intensity, and found good agreement with the results calculated from the rate equation.