Strong-field effects in bichromatic laser-induced collisional energy transfer

We discuss a scheme suitable for the study of strong-field effects on the excitation spectrum of the laser-induced collisional energy-transfer process. The use of a weak radiation field, to induce the interatomic transition, and a strong radiation field, to modify the energy-level position, is found to give rise to a splitting of the resonance peak. The position and the relative intensity of the two spectral components are strongly dependent on the intensity and detuning of the strong field. Line-shape calculations performed for the Eu-Sr system show that the effect is expected to be detectable even for moderate intensities of the strong field. © 1995 The American Physical Society.