Pulse-shape dependence in population inversion with frequency chirping

Krishna Myneni, Michael E. Crenshaw, Mark J. Bloemer

Angelo Turrin

Sofiane Grira, Nadia Boutabba, Hichem Eleuch

We perform a theoretical analysis of the Bloch equations of a two-level atom with dephasing. Exact analytical solutions with two different chirped and time-dependent detuned laser pulses are derived. The atomic population inversion as well as the coherence are explored for different initial populations. We show that the stationary population inversion can be controlled.

Q. Q. Xu, D. Z. Yao, Xiaona Liu +2 more

We investigate the solitary propagation effect of a well-defined chirped femtosecond laser pulse in a resonance-absorbing medium which is modeled by a two-level quantum dot ensemble. Employing full time-dependent and space-dependent Maxwell-Bloch equations, the evolution of the pulse and the population inversion as well as the spectrum are obtained. The results reveal that the special chirped pulse can retain its shape and resist breakup while propagating through the absorbing medium. Besides, the spectrum does not exhibit obvious broadening but the central and near-central frequency components tend to vanish. Moreover, the stable soliton formed by the special chirped-pulse design based on stimulated Raman adiabatic passage does not obey the area theorem.

Avijit Datta

Sofiane Grira, Nadia Boutabba, Hichem Eleuch

We theoretically investigate a two-level atom driven by a time-dependent external field with a generalized double exponential temporal shape, in the presence of dephasing. Therefore, we provide exact analytical solutions for the population inversion, the real and the imaginary parts of the coherence for a family of chirped and time-dependent laser waveforms. We demonstrate that the remaining atomic population inversion can be controlled by the manipulation of the pulse’s shape structure.