arXiv:nlin/0411010 · Physical Review A

Models for optical solitons in the two-cycle regime

Hervé Leblond, François Sanchez

Published Jan 23, 2003• 99 citations

Abstract

We derive model equations for optical pulse propagation in a medium described by a two-level Hamiltonian, without the use of the slowly varying envelope approximation. Assuming that the resonance frequency of the two-level atoms is either well above or well below the inverse of the characteristic duration of the pulse, we reduce the propagation problem to a modified Korteweg--de Vries or a sine-Gordon equation. We exhibit analytical solutions of these equations which are rather close in shape and spectrum to pulses in the two-cycle regime produced experimentally, which shows that soliton-type propagation of the latter can be envisaged.

DOI: 10.1103/physreva.67.013804

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