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zheng89120
Mar26-11, 01:05 AM
1. The problem statement, all variables and given/known data

Consider a three level system, the time-dependent perturbation is:

W(t) = W cos(wt) e^(-t^2/T^2)

at time t=-infinity, it's in the ground state (w/ E1)

the pertubation frequency is:

w = (w21+w31)/2

non-zero matrix elements are: <1|W|2>=<1|W|3>=<2|W|1>=<3|W|1>=\gamma

Show that the eigenstate is:

|\psi(t)> = e-iw1t [ ||\psi>
-iAe-iw21t |\psi>
-iAe-iw31t |\psi3> ]


2. Relevant equations

fourier transform of a gaussian

3. The attempt at a solution

tried to take fourier transform of cos wt * e^(-t^2/T^2), but couldn't get the form Aeiwt |\psi2/3>