Optical Soliton Like-Pulses in Ring-Cavity Fiber Lasers of Carbon Nanotubes

A nonlinear schrödinger system in the optical fiber laser communications, with the second-order dispersion coefficient, mode locking with the use of an saturable absorber, including the gain dispersion, losses for the cavity and fiber, group-velocity dispersion, self-phase modulation and two-photon absorption, is analyzed through the G′/G-expansion scheme. It is the governing system of ring-cavity fiber laser using carbon nanotubes for passive mode locking. Soliton solutions for that system are found to be of different kinds: kink, inverse kink, tangent and cotangent forms solitary wave. The obtained optical soliton solutions are very interesting and valuable in the field of research pertaining to nonlinear optics.