Half-optical-cycle damped solitons in quadratic nonlinear media

Abstract

In this paper, Using a classical model of the radiation-matter interaction, we show that the propagation of (1 þ 1) dimensional few-optical-cycle pulses in quadratic nonlinear media, taking moderate absorption into account, can be described by the Korteweg-de Vries-Burgers' (KdVB) equation without using the slowly varying envelope approximation. To fulfill this purpose we use the reductive perturbation method and consider the long-wave approximation, assuming that the characteristic frequency of the pulse is much lower than the resonance frequency of the atoms. We also study both analytical and numerical solution of the KdVB equation describing damped few-optical-cycle soliton propagation.

Linear and nonlinear waveguiding of few-cycle optical solitons in a planar geometry

“…x = εξ, (26) in the cladding only, with the waveguide core being assumed to be too narrow to allow variations in the ξ direction. The electric field is expanded in a power series of ε as E = εE 1 + ε 2 E 2 + • • •, and so on.…”

“…Since the standard SVEA is not valid for describing the spatiotemporal evolution of ultrashort pulses containing only a few oscillations of the optical field, several research groups derived alternative approaches for describing the physics of such phenomena; see a list of recent relevant works in this growing area [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28]. However, though most of the past research interest in the study of propagation of FCPs was confined to the simplest two-level atomic system (see the review [13]), a more realistic description of the ultrashortsoliton propagation in optical media by taking into account an arbitrary number of atomic levels was also put forward [29][30][31].…”