Physical Review Letters

Spectral response and propagational instability for pump-probe propagation in a two-level medium

Michael E. Crenshaw, C. M. Bowden

Published Sep 2, 1991• 4 citations

Abstract

The interaction of a strong nearly resonant cw pump laser and a weak cw probe laser in a medium consisting of two-level atoms was studied by numerical integration of the Maxwell-Bloch equations. With propagation into the optically thick medium, the numerically calculated probe gain spectrum deviates substantially from one calculated by a four-wave-mixing formulation of coupled-wave theory with an undepleted pump. For probe frequencies inside the modified gain region, the laser field, initially in an unstable steady-state condition, evolves to a stable solution of the sine-Gordon equation.

DOI: 10.1103/physrevlett.67.1226

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