Soliton pulse propagation in averaged dispersion-managed optical fiber system

The dynamics of nonlinear pulse propagation in an averaged dispersion-managed soliton system is governed by a variable coefficient nonlinear Schrodinger equation (NLSE). For a special set of parameters the variable coefficient NLSE is completely integrable. The same variable coefficient NLSE is also applicable to optical fiber systems with phase modulation or pulse compression. For such variable coefficient NLSE, solitary waves have been computed earlier in the literature either by the inverse scattering transform or the Backlund transformation. The Hirota bilinear method is shown to be applicable here too, and this modified format is employed to compute the exact bright and dark soliton solutions and the periodic waves solutions. The analysis is also extended to the coupled variable coefficient NLSEs. The merit of the Hirota bilinear approach is demonstrated clearly as periodic and solitary waves are obtained even for nonintegrable coupled systems. The validity of the new solutions is verified directly and independently by the software Mathematica.