Define a two-level system:
Find a transformation matrix suitable for applying the rotating-wave approximation, assuming that a field of frequency
couples the lower state 1 to the upper state 2:
For this system,
RotatingWaveTransformMatrix can guess that state 1 is the lower state and state 2 is the upper state, so it is not necessary to specify the transition:
Here is an example with three levels and two fields.
Define a three level system:
Find a transformation matrix for the RWA assuming that
Energy[a]<Energy[b]<Energy[c]:
If, instead, we assume that
Energy[a]<Energy[c]<Energy[b], we obtain a different transformation matrix: