Chirped double-kink and fractional-transform solitons in an optical gain medium with two-photon absorption

Abstract

We demonstrate that localized gain induces chirped double-kink, fractional-transform, bell and kink-type solitons in a nonlinear optical medium in the presence of two-photon absorption (TPA). We have seen that by modulating the properties of the gain medium one can control the width of double-kink solitons. It is shown that the nonlinear chirp associated with optical solitons is directly proportional to the intensity of the wave. We have further investigated the variation of gain with the TPA coefficient and found that the gain is transversally localized and its amplitude is directly proportional to the value of the TPA coefficient.