  Wave-speed management of soliton pulses in a nonlinear metamaterial
exhibiting a rich variety of physical effects that are important in a wide
range of practical applications, is studied both theoretically and numerically.
Ultrashort electromagnetic pulse transmission in such inhomogeneous system is
described by a generalized nonlinear Schreodinger equation with space-modulated
higher-order dispersive and nonlinear effects of different nature. We present
the discovery of three types of periodic wave solutions that are composed by
the product of Jacobi elliptic functions in the presence of all physical
processes. Envelope solitons of the dipole, bright and W-shaped types are also
identified, thus illustrating the potentially rich set of localized pulses in
the system. We develop an effective similarity transformation method to
investigate the soliton dynamics in the presence of the inhomogeneities of
media. The application of developed method to control the wave speed of the
presented solitons is discussed. The results show that the wave speed of
dipole, bright and W-shaped solitons can be effectively controlled through
spatial modulation of the metamaterial parameters. In particular, the soliton
pulses can be decelerated and accelerated by suitable variations of the
distributed dispersion parameters.
