The Influence of Level Degeneracy on the Self-Induced Transparency Effect

Self-induced transparency effects are examined in an absorbing medium having degenerate optical transitions. Undistorted propagating light pulses exist under restrictive conditions for $j\rightleftharpoons j$ transitions ($j>\mathrm{}0\mathrm{}$) and for 0 ⇌ 1 and $\frac{1}{2}\rightleftharpoons \frac{3}{2}$. Pulses which propagate without energy loss for any transition ${j\rightleftharpoons j}^{\prime }$ also include zero-degree pulses defined as $\int \mathcal{E}\mathrm{}(z,t)dt=0\mathrm{}$.