Tapered 2π pulses in a medium with inhomogeneous broadening of the resonance absorption line

Hari Prakash, G. S. Bhatnagar

V. M. Arutyunyan, V. O. Chaltykyan

A E Dmitriev, Oleg M. Parshkov

Xiangyang Yu, Wei Liu, Cheng Li

We present a numerical method for solving the Maxwell-Bloch equations describing pulse propagation for a two-level medium. The method is accurate, efficient, stable, and well suited for this type of simultaneous equations. By applying the numerical scheme we investigate the evolutions of pulse area, pulse propagation, pulse velocity, and spectral shapes under both homogeneous and inhomogeneous broadening conditions. The results show that the area evolution and pulse-reshaping procedure are significantly influenced by detuning and inhomogeneous line shape, which also impact the oscillation tail and pulse peak. In addition, the pulse-peak traces indicated the pulse velocity always increases with greater deviation in pulse-area value from the value 2\ensuremath{\pi}. We also demonstrate the pulse velocity increased for a larger detuning or a wider inhomogeneous line shape. Furthermore, the spectral feature shows that pulse spectra evolve into an oscillating shape.

A E Dmitriev, Oleg M. Parshkov

The results of numerical simulations are outlined for the evolution of a 0π pulse in a medium with an inhomogeneously broadened quantum transition neglecting irreversible relaxation. A rule is formulated for the prediction of the 0π-pulse structure at long distances, which relies on the notion of the 0π-pulse area as the area under the curve of the modulus of its envelope. Analytical relations between the duration, the peak value, and the propagation velocity are given for the 0π pulse of the breather type.

Evald E. Fradkin, V V Kozlov, Maxim Voronov

An exact semiclassical solution to the problem of the simultaneous propagation of weak and strong pulses interacting with adjacent transitions of a three-level V-scheme was found. The homogeneous and inhomogeneous broadening of the absorption lines of a gaseous medium was examined. It was shown that the computational formulas are suitable for any profile and area under the strong pulse, although numerical calculations were performed for a 2π pulse. The results were compared with those obtained by integration of the system of equations for the density matrix (carried out in the τ 3 ≪ τ 1 approximation, where τ 3 and τ 1 are the durations of the weak and strong pulses, respectively) and also with a theoretical estimate. A qualitative explanation of the phenomenon mentioned above was proposed.