Polarization spectroscopy of Rb and Cs

Theoretical calculation of ⁸⁵Rb and ¹³³Cs D₁ signals in polarization spectroscopy is presented by using the method of velocity-selective optical pumping in a four-level system. Since good agreement between theory and experiment has been found in Na D₁ polarized signals, the theoretical calculation can be also applied to Rb and Cs D₁ lines. Rb and Cs atoms have higher total angular momentum F in the hyperfine structures than Na atom and then the calculation is more complicated. The relative signal intensities in polarization spectroscopy are compared with those in saturation spectroscopy.