Soliton propagation is modeled in a tapered photonic crystal fiber for various taper profiles with the purpose of optimizing the soliton self-frequency shift (SSFS) in such geometries. An optimal degree of tapering is found to exist for tapers with an axially uniform waist. In the case of axially nonuniform waists, an additional enhancement of the SSFS is achieved by varying the taper waist diameter along its length in a carefully designed fashion in order to present an optimal level of group-velocity dispersion to the soliton at each point, thus avoiding the spectral recoil due to the emission of dispersive waves. In doing so, the increased nonlinearity and dispersion engineering afforded by the reduction of the core size are exploited while circumventing the limitation imposed on the soliton redshift by the associated shortening of the red zero-dispersion wavelength.
© 2009 Optical Society of America
Fiber Optics and Optical Communications
Original Manuscript: July 9, 2009
Revised Manuscript: September 8, 2009
Manuscript Accepted: September 8, 2009
Published: October 16, 2009
A. C. Judge, O. Bang, B. J. Eggleton, B. T. Kuhlmey, E. C. Mägi, R. Pant, and C. Martijn de Sterke, "Optimization of the soliton self-frequency shift in a tapered photonic crystal fiber," J. Opt. Soc. Am. B 26, 2064-2071 (2009)