Self-similar pulses in coherent linear amplifiers.

Department of Electrical and Computer Engineering, Dalhousie University, Halifax, NS, B3J 2X4, Canada.
Optics Express (Impact Factor: 3.53). 05/2011; 19(10):9750-8. DOI: 10.1364/OE.19.009750
Source: PubMed

ABSTRACT We discover and analytically describe self-similar pulses existing in homogeneously broadened amplifying linear media in a vicinity of an optical resonance. We demonstrate numerically that the discovered pulses serve as universal self-similar asymptotics of any near-resonant short pulses with sharp leading edges, propagating in coherent linear amplifiers. We show that broadening of any low-intensity seed pulse in the amplifier has a diffusive nature: Asymptotically the pulse width growth is governed by the simple diffusion law. We also compare the energy gain factors of short and long self-similar pulses supported by such media.

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