Analytic calculation of the lineshapes in polarization spectroscopy of rubidium

This paper reports on analytic calculations of the lineshapes for polarization spectroscopy of rubidium atoms. Under the use of a weak circularly polarized pump beam, the time-dependent population of each magnetic sublevel was obtained analytically from the rate equations up to the lowest order of the pump beam intensity, and the associated circular birefringence experienced by a counterpropagating probe beam was calculated. In particular, analytic forms of the polarization spectroscopy spectra were obtained for Rb-87 and Rb-85 atoms using the mean transit time crossing the pump beam, and the analytic results were compared with the numerical data, experimental results and Nakayama model's results, showing a good agreement one another. (c) 2008 Elsevier B.V. All rights reserved.