Dynamics of blueshifted floating pulses in gas-filled hollow-core photonic crystal fibers

Abstract

Frequency blueshifting was recently observed in light pulses propagating on gas filled hollow-core photonic crystal fibers where a plasma has been produced due to photoionization of the gas. One of the propagation models that is adequate to describe the actual experimental observations is here investigated. It is a nonlinear Schrödinger equation with an extra term, to which we applied a self-similar change of variables and found its accelerating solitons. As in other NLS related models possessing accelerating solitons, there exist asymmetrical pulses that decay as they propagate in some parameter region that was here well defined.

Analytic description of laser pulse propagation in gas-filled hollow-core photonic crystal fibre

“…It was shown both experimentally and theoretically that through ionization-induced optical nonlinearity in HC-PCFs, the spectrum of the pulse can be shifted toward higher frequencies [4]. This is caused by free-electron generation in the gas and leads to a negative step in the refractive index and therefore to soliton self-frequency blueshift [4][5][6][7][8][9][10][11][12]. This phenom enon is the opposite of the well-known stimulated Raman self-scattering (SRSS) situation [13][14][15][16][17][18][19][20].…”