  We present the discovery of two types of multiple-hump soliton modes in a
highly dispersive optical fiber with a Kerr nonlinearity. We show that
multi-hump optical solitons of quartic or dipole types are possible in the
fiber system in the presence of higher-order dispersion. Such nonlinear wave
packets are very well described by an extended nonlinear Schrodinger equation
involving both cubic and quartic dispersion terms. It is found that the third-
and fourth-order dispersion effects in the fiber material may lead to the
coupling of quartic or dipole solitons into double-, triple-, and multi-humped
solitons. We provide the initial conditions for the formation of coupled
multi-hump quartic and dipole solitons in the fiber. Numerical results
illustrate that propagating multi-quartic and multi-dipole solitons in highly
dispersive optical fibers councide with a high accuracy to our analytical
multi-soliton solutions. It is important for applications that described
multiple-hump soliton modes are stable to small noise perturbation that was
confirmed by numerical simulations. These numerical results confirm that the
newly found multi-soliton pulses can be potentially utilized for transmission
in optical fibers medium with higher-order dispersions.
