Dynamical resonances and the topology of the multiphoton adiabatic passage

We analyze adiabatic transfer processes in two-level systems driven by bichromatic delayed laser pulses. We show that the robust transfer of atomic population and the exchange of momentum with the laser fields can be understood on the basis of topological properties of dressed energy surfaces that are determined by dynamical resonances. The analysis shows a topological quantization of the multiple absorption and emission of photons.