Theory of lineshapes in resonance scattering spectra

Leonardo Angeloni, Pier Francesco Fracassi, Raffaele Guido Della Valle

Alexandra Nemeth, Franz Milota, Tomáš Mančal +3 more

Yitzhak Rabin, A. Ben‐Reuven

Lineshapes of three-level resonance Raman scattering and two-level resonance fluorescence, homogeneously broadened by collisions, in the presence of arbitrarily strong coherent radiation, are studied by means of a tetradic (density-matrix) scattering theory. In the case of medium coupling strength V L to the radiation field (where T 2 -1 <or=V L << tau c -1 , with T 2 and tau c being the coherence damping and collision times, respectively) the Mollow lineshape (1977) for resonance fluorescence is rederived, with proper T 2 and population cross-relaxation effects included. In particular it is shown that relaxation through intermediate non-resonant levels can considerably alter the lineshape in resonance fluorescence. In the case of strong coupling (V L >or approximately= tau c -1 ) the collision rates are modified by the applied field (optical collisions). It is shown that, whereas in self attenuation spectra optical collision rates can be obtained only from line intensity or line wing measurements, in resonance scattering these rates are directly obtained from linewidth measurements.

J.A. Hermann, S. Swain

P. L. Knight

A theoretical analysis of the time development of spontaneous Raman scattering lineshapes is presented. Particular attention is paid to transients caused by the sharp turn-on of the laser fields. The author examines the breakdown of lowest order perturbative ideas, the role of induced widths and shifts and of Rabi oscillations in final-state spectra for large pump intensities.

M. G. Zakaraya, Gia G. Maisuradze