Action Of Third-order Dispersion Research Articles

Chirp-Induced Channel of an Airy Pulse in an Optical Fiber Close to Its Zero-Dispersion Point

We investigate the dynamics of a chirped Airy pulse in a fiber under the action of third-order dispersion. We found an interesting phenomenon in which the pulse is focused and where the pulse profile changes slowly within a distance of several dispersion lengths, which is named a channel. The amplitude and the length of the channel depends on the chirp parameter. The underlying physical mechanism for this phenomenon is also discussed.

Properties of compact bright pulse in long optical waveguide: Higher-order effects

The properties of the compact bright (CB) pulse propagating in the long optical waveguide under the action of third-order dispersion (TOD), time derivative of the pulse envelope and first moment of the nonlinear response function of the waveguide known as the Raman term are investigated. From the dispersionless nonlocal Nonlinear Schrodinger equation (NLS) describing the propagation of light beam in the waveguide with nearly instantaneous nonlinear response and extended either by the TOD or the time derivative of the pulse envelope, the exact analytical expressions of CB pulse are derived. It appears that although the TOD does not affect the pulse amplitude, shape and width, it induces the deviation of the pulse velocity from the group velocity of the wave packet with a magnitude depending of the pulse frequency. Similarly, the presence of the time derivative of the pulse envelope affects the pulse parameters namely the shape, width and constant of propagation and also induces the self-steepening of the CB pulse. As for the Raman term, the result from the perturbation approach shows that the CB pulse experiences a self-frequency shift linearly proportional to the distance of propagation of the pulse. Although some of the obtained results are qualitatively similar to those previously exhibited by the bright soliton, the analytical expressions are quite different. The accuracy of these analytical results is checked trough numerical simulations of the appropriated extended nonlocal NLS equation and the wave spectrum.

Inversion and tight focusing of Airy pulses under the action of third-order dispersion

By means of direct simulations and theoretical analysis, we study the nonlinear propagation of truncated Airy pulses in an optical fiber exhibiting both anomalous second-order and strong positive third-order dispersions (TOD). It is found that the Airy pulse first reaches a finite-size focal area as determined by the relative strength of the two dispersion terms, and then undergoes an inversion transformation such that it continues to travel with an opposite acceleration. The system notably features tight focusing if the TOD is a dominant factor. These effects are partially reduced by Kerr nonlinearity.

Dynamics of ultrashort pulses near zero dispersion wavelength

The adiabatic dynamics of solitons under the action of third-order dispersion (TOD), the Raman effect, and self-steepening is studied. Using equations that describe the evolution of the pulse parameters, it is shown that the interplay between these effects results in nontrivial pulse dynamics. It is found that positive TOD slows down the self-frequency shift. The theory also describes the eventual suppression of the self-frequency shift in fibers with negative TOD that was recently observed in experiments and described theoretically. The relations of our results to supercontinuum generation are discussed.

Timing jitter in ultrahigh-speed dispersion-managed soliton systems

An analytical theory is presented which demonstrates the timing jitter induced by amplifier noise in ultrahigh-speed dispersion-managed soliton systems when the Raman effect and third-order dispersion (TOD) are considered. The analysis indicates that Raman jitter remains a potential problem for picosecond and subpicosecond pulses. Positive residual TOD can enhance the timing jitter caused by the combined action of TOD and Raman effect, while vice versa for negative residual TOD.