The model five-level system. The dipole matrix elements (in a.u.) coupling neighboring levels are shown in the boxes. The background (intruder) state ∣5⟩ is coupled weakly to the top of the strongly sequentially coupled anharmonic progression ∣1⟩–∣4⟩.
(a) Population dynamics in the model five-level system induced by the resonant Gaussian pulse . Short-dashed thin lines: reference adiabatic dynamics in the intruder state decoupled effective four-level system. Bold lines: leaking dynamics in the fully coupled system. The individual states are indicated. Intruder population is dashed for highlighting. (b) The corresponding adiabatic Floquet quasienergy correlation diagrams. Full lines: intruder state ∣5⟩ decoupled (adiabatic); broken lines: fully coupled (diabatic). Asymptotic states are indicated near the right margin.
Total control fields, correction fields, and associated population dynamics in the model five-level system for avoided-crossing related correction fields . Column (a): two Lorentzian pulses placed at the crossing points and . Column (b): four Lorentzian pulses placed at the crossing points . The times are indicated as short-dashed vertical lines. Fields are shown in gray; envelopes of their constituent fields are overlaid as black lines. Individual populations are drawn as in Fig. 2(b); intermediate state populations are omitted for clarity of presentation.
Total control fields, correction fields, and associated population dynamics in the model five-level system for population-branching related correction fields. Column (a): the best analytically represented counterdiabatic control field obtained as a superposition of three Lorentzians put into the interval (see text). Column (b): similar to (a), but for a superposition of three Gaussians. Column (c): control field obtained by careful optimal control improvement of (b) (see text). The extension of is indicated by short-dashed vertical lines. All other graph properties are as in Fig. 3.
Control fields obtained by brute-force optimal control, and corresponding Fourier spectra and population dynamics. The short-dashed vertical lines at 0.004 25, 0.004 50, and shown in the panels in the middle row indicate the zero-order 1-PT frequencies , , and along the anharmonic ladder. The 3-PT frequency coincides with . The lines near indicate the target-intruder transition frequency . Column (a): from Fig. 4(a) used as input field. Column (b): control field obtained from (a) by optimal control with strong reduction of (, variable in several iterations). Column (c): control field obtained from (b) with strong fluence reduction (, variable in several iterations). Other graph properties are as in Fig. 3.
Article metrics loading...
Full text loading...