Methodology of LC-SLM for filtering and phase spectral recovering of GVD and SPM in the ultra-short pulse propagation through single-mode fiber

Abstract

The performance of ultra-short pulse propagation through single-mode fiber (SMF) is degraded due to linear and nonlinear phenomena like fiber loss, group velocity dispersion (GVD), and self-phase modulation (SPM). Since diffraction phenomena and transmittance functions of the optical devices affect the magnitude and phase of a propagated ultra-short pulse, it is necessary to build-up an approach in order to optimize such limitations. In the paper, a simulation of Gaussian pulse propagation through SMF and 2-f line spatial configuration is presented. The effects of GVD and SPM are generated by split-step Fourier method (SSFM) to solve the nonlinear Schrodinger equation (NLSE). For the spatial configuration, Fresnel's approximation and the transmittance functions for optical elements such as gratings and lens are considered. To manipulate and recover spectral phases of the ultra-short pulse, an approach applied over a liquid crystal spatial light modulator (LC-SLM) as a phase modulator and spectral filter is proposed. The preliminary results show that the ultra-short pulse propagation in SMF is affected in presence of GVD and SPM just at the same time. In the second simulation, the interaction for a propagated ultra-short pulse through a 2f-line spatial configuration is described. The input spectral phases were manipulated by a LC-SLM at the Fourier's plane, obtaining a flat phase. In the third simulation, the spectral components from a pulse were filtered by fixed masks, implemented on the LC-SLM as a low-pass and band-pass filter, respectively.