Some Results on Coherent Radiative Phenomena with0πPulses

Abstract

The propagation behavior of nontrivial $0\pi$ pulses [$\int {-\infty }^{\infty }\mathcal{E}\mathrm{}(t,z)dt=0\mathrm{}$, $\int {-\infty }^{\infty }{\mathcal{E}}^2\mathrm{}(t,z)\mathrm{dt}>\mathrm{}0\mathrm{}$] in attenuating media is examined. It is found that under appropriate conditions $0\pi$ pulses exhibit anomalously low absorption which is a direct consequency of atomic coherence. Specific analytical results valid for an unbroadened medium are presented, while the corresponding solutions for an inhomogeneously broadened resonance are calculated numerically. These two results are consistent in the limit of $T_2^{*}\to \infty$. Furthermore, the influences of $T_2$, $T_2^{*}$, and level degeneracy on the characteristics of propagation are determined. Finally, the behavior of more general $0\pi$ pulses is studied. The criteria for the production of $0\pi$ pulses are qualitatively established by numerical methods, and the influence of the relative phase of pulse pairs on propagation is examined. The latter indicates a method for the measurement of relative pulse phase.