Excitation spectra for the V configuration of a three-level atom in resonance with two laser fields

The excitation spectrum is calculated for a three-level atom interacting with two strong electromagnetic fields. The two fields are in resonance with the atomic transition frequencies from the ground state to the two excited states. The excitation spectrum consists of a central peak and two pairs of side bands for each of the two transitions. If the decay rates of the two excited states are equal a relatively simple closed form expression is derived for the excitation spectrum. For unequal decay rates numerical methods are used to determine the excitation spectrum for selected special cases.