arc.calculations_atom_single.ShirleyMethod.calcTransitionProbability#

ShirleyMethod.calcTransitionProbability(tevals)[source]#

Calculates the time-dependent transition probability.

Note that the calculation assumes all population is in the target state at time \(t=0\) and that this probability is averaged over initial phases of the driving field, therefore is primarily valid in the CW driving case.

This function implements Eq. 18 of [1]_ and is primarily for calculation the Rabi flops in population under high driving fields.

Parameters:

tevals (float or numpy.ndarray) – Times to evaluate the transition probability. In units of seconds. Input is coerced to a numpy array.

Returns:

Transition probability to go from the target state

to any state in the basis, as a function of t. Output tensor shape is of the form (tevals, efields, freqs, floquet_basis), where efields, freqs, and floquet_basis sizes are taken from the result of the diagonalise() function.

Return type:

numpy.ndarray

References: .. [1] J. H. Shirley, Physical Review 138, B979 (1965)