Three-level system in an asymptotically strong field

I. V. Lebedev

Martin Bodo Plenio

The spectrum of resonance fluorescence from laser-driven multi-level systems is investigated and especially its asymptotic frequency dependence in the wings. Analytical results are presented and the transitions within multilevel systems are classified into three categories according to the asymptotic frequency dependence of their spectra. Under certain conditions an arbitrarily fast asymptotic fall-off behaviour of the spectrum is found which, for intermediately strong driving fields, leads to subnatural linewidths. Numerical examples are presented to illustrate the analytical results.

Z. K. Yankauskas, G. I. Valyukenas

Stephen D. Clow, Carlos A Trallero-Herrero, Thomas H. Bergeman +1 more

We demonstrate strong-field population inversion in a three-level system with single and multiphoton coupling between levels using a single shaped ultrafast laser pulse. Our interpretation of the pulse shape dependence illustrates the difference between sequential population transfer and adiabatic rapid passage in three-level systems with multiphoton coupling between levels.

Victor P. Kochanov, Julia V. Maltseva

A stationary distribution of populations in a three-level quantum system interacting with three intense monochromatic fields resonant to two allowed and one forbidden transition is determined for three possible configurations of the considered system. The obtained algebraic expressions for populations of levels are exact within the frameworks of RWA and dependent on the phases of fields even in the limit of strong field intensities. The latter circumstance causes the absorption line profile to be noisy due to random phase modulation of fields. The sets of parameters of the system and field are founded at which the populations of all the levels are equal to 1/3 also with the regions where a resonance-like dependence of level populations on the difference of field phases takes place.

Lev Deych