Interactions between a three-level atom and two amplitude-fluctuating lasers are studied theoretically. One interesting feature of the interactions is the influence of the finite laser bandwidth and the two-laser cross-bandwidth on the absorption rate into the third level. As an example, it is shown how the partially saturated absorption process depends on both the autocorrelated and cross-correlated laser bandwidths.
N. C. Wong and J. H. Eberly, "Multiphoton absorption in the presence of two finite-bandwidth lasers," Opt. Lett. 1, 211-213 (1977)