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We have studied the impact of the higher-order effects: intrapulse Raman scattering (IRS), third-order of dispersion (TOD) and self-steepening (SS) on pulsating solutions, moving fronts and stationary solutions of the complex cubic–quintic Ginzburg–Landau equation (CCQGLE) found in Tsoy and Akhmediev (2005) as well as on the solutions presented in Uzunov et al. (2014). The applied basic equation generalizes the CCQGLE with the IRS, TOD and SS effects. A finite-dimensional dynamical system has been derived using the method of moments. Applying the derived dynamical system alongside with the numerical solution of the generalized CCQGLE performed by means of the fourth-order Runge–Kutta interaction picture method we have found that the influence of IRS and SS is stronger than the impact of TOD for the solutions of Tsoy and Akhmediev (2005). Perturbed pulsating solutions, moving fronts and stationary solutions in the presence of IRS, SS and TOD have been numerically observed. They exist up to some critical values of the parameters of perturbations. For the values of parameters larger than the critical ones the pulsating solutions are transformed into stable stationary solutions or unstable solutions. New localized fluctuating and stationary solutions have been obtained for fairly large values of parameters of IRS and TOD, respectively. The transformation of the stable stationary solution of Uzunov et al. (2014) under the influence of SS into pulsating solution has been numerically observed. [ABSTRACT FROM AUTHOR]

Abstract: Single-mode fiber optical system with saturable amplification, saturable losses and spectral filtering as proposed by Rozanov and Fedorov (1998) is studied. The system of ordinary differential equations (ODE’s) that can help investigation of the original physical system is proposed. It allows calculation of linear and nonlinear fixed points as well as the study of their stability, so it can be used for analysis of coherent structures and their classification. Derived system of ODE’s extends the earlier one proposed by van Saarloos and Hohenberg (1992) , for the analysis of coherent structures of the qubic–quintic Ginzburg–Landau equation, by including additionally the temporal dependences of the gain and losses. In order to verify it, it was applied to the earlier considered cases of fast and slow changes in the amplification and losses. Earlier obtained localized structures namely pulses, have been observed via numerical solution of the proposed system. In addition, new families of fronts have been identified. [Copyright &y& Elsevier]

Abstract: Two coupled nonlinear Schrödinger equations describing the transmission of subpicosecond pulses in strongly birefringent fibers with Raman scattering are studied by a symmetry reduction method and a perturbative technique. Two families of approximate vector solitary waves are obtained. Reduction of the Raman frequency shift in birefringent fibers is established. [Copyright &y& Elsevier]