Showing 2 results for Modulation Instability
H. Pakarzadeh, A. Zakery,
Volume 4, Issue 1 (1-2010)
Abstract
In this paper, by including Raman scattering in the coupled-mode equations, the scalar modulation instability in photonic crystal fibers is investigated. The evolution of the pump, Stokes and anti-Stokes waves along the fiber as well as the conversion efficiency for two cases, with and without Raman effect, are studied. The effect of anti-Stokes seed and the pump depletion on the evolution of Stokes wave is also considered. Moreover, the parametric gain when it is affected by Raman gain is dealt with. The results show that it is important to take into account Raman scattering, especially for wide-bandwidth parametric amplifiers which results in an asymmetric spectrum and more amplification of the Stokes wave.
Morteza A. Sharif,
Volume 14, Issue 2 (12-2020)
Abstract
In this paper, an all optical graphene-based modulation approach is proposed induced by Modulation Instability (MI). The device structure is based on graphene sheets transferred on the both arms of a Mach-Zehnder interferometer to support amplified Surface Plasmon Polaritons (SPPs). Due to the nonlinear nature of MI to interfere in the modulation process, the proposed approach leads to an enhanced performance in comparison to the conventional Mach-Zehnder modulators; using a low power cw driving beam (~20 µW at λ=50 µm), a high speed modulation rate (~2 Tpps) and subsequently, a high depth (89%), wideband modulation (~81 GHz) can be resulted. Since the MI is a pre-state to the chaotic regime, the modulator can be also used for secure optical communication.