2000/06/08 by V. Delgado, V Delgado, J. M. Gomez Llorente +1 · 3 citations
Computer Science · Physics and Astronomy · #Quantum Information and Cryptography #Quantum optics and atomic interactions #cond-mat.other #quant-ph #stochastic dynamics and bifurcation
paper · pdf · doi:10.1088/0953-4075/33/23/312
published as J. Phys. B, 33 (2000) 5403 · 14 pages, LaTeX, 2 figures, acknowledgments added
arxiv created 2000/06/08 · openalex publication_date 2000/11/23 · arxiv updated 2010/07/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
The time evolution of driven two-level systems in the far-off-resonance regime is studied analytically. We obtain a general first-order perturbative expression for the time-dependent density operator which is applicable regardless of the coupling strength value. In the strong-field regime, our perturbative expansion remains valid even when the far-off-resonance condition is not fulfilled. We find that, in the absence of dissipation, driven two-level systems exhibit coherent population trapping in a certain region of parameter space, a property which, in the particular case of a symmetric double-well potential, implies the well known localization of the system in one of the two wells. Finally, we show how the high-order harmonic generation that this kind of system displays can be obtained as a straightforward application of our formulation.