Non-adiabatic coupling and adiabatic population transfer in quantum   molecular systems
  We show that a counter-intuitive pulse sequence leads to adiabatic passage between the vibrational levels of three harmonic potentials through parallel dark states in adiabatic approximation. However, the adiabatic assumptions break down for very intense pulses and non-adiabatic couplings result in the population transfer by light-induced potential shaping. 
Ignacio R. Sol\'a and Vladimir S. Malinovsky