TEMPORAL PULSE BROADENING DUE TO AMPLIFIER-PRODUCED FREQUENCY NARROWING IN THE SMALL-SIGNAL-GAIN LIMIT

摘要

A temporally short radiation pulse amplified in the small-signal-gain case may broaden out in time (and space) due to a narrow bandpass amplifier, spectral narrowing, or frequency dispersion in the medium. An approximate solution for the output temporal width is presented assuming a Gaussian waveform for the input pulse and a homogeneous Lorentzian gain profile for the amplifier. This particular approximation for the frequency width agrees with the rate equation treatment of frequency narrowing by Casperson and Yariv.