Steady-state pulses in degenerate swept-gain amplifiers

Valentin P. Petrov, Wolfgang Rudolph

Dieter Pohl, Martin Maier, W. Kaiser

R. Bonifacio, F. A. Hopf, Pierre Meystre +1 more

The steady-state behavior of amplifiers in which the excitation is swept at the speed of light is discussed in the semiclassical approximation. In the present work we examine the case where the decay time of the population is comparable to that of the polarization. Pulse propagation is shown to obey a generalized sine-Gordon equation which contains the effects of atomic relaxations. The analytical expression of the steady-state pulses (SSP) gives two threshold conditions. In the region of limited gain the SSP is a broad pulse with small area which can be obtained by small signal theory. In the second region of high gain the SSP is the superradiant $\ensuremath{\pi}$ pulse. Its pulse power is not limited as in usual superradiant theory because, as we show, for a swept excitation the cooperation-length limit does not exist.

Mark D. Rotter, Roger A. Haas

J.A. Hermann

Frederic A. Hopf, Edward A. Overman

We investigate, theoretically, fluctuations in coherent steady-state pulses in a nonlinear swept-gain amplifier. In the superradiant steady state, we predict large energy and power fluctuations which are found to be largely independent of the magnitude of the fluctuating force.