Resonant two-photon interference spectra induced by a bichromatic field in the excited state of a three-level atom

The interference spectra arising from the competition between a spontaneous process and an induced one by two laser fields, which interact on two-photon resonance with a three-level atom in the Lambda configuration have been considered. In the low intensity limit of both laser fields, the frequency profiles of the two peaks, which arise from the spontaneous and induced processes, respectively, cancel each other out completely at the centre of the line for zero detuning and at the finite values of the detuning as well. At those frequencies, the fluorescent light totally disappears. The interference spectra arising from the absorption of a laser photon by the ground state of the atom consists of two peaks describing the induced processes of absorption and stimulated emission, respectively.