scispace - formally typeset
Journal ArticleDOI

Effect of lower and upper parabolic dips in refractive index profile on performance of coaxial fiber Raman gain amplifier

01 Mar 2016-Optical Engineering (International Society for Optics and Photonics)-Vol. 55, Iss: 3, pp 036103-036103
Abstract: An investigation on the effect of practically possible upper and lower parabolic dips in the refractive index profile of the inner core of the coaxial fiber Raman gain amplifier is reported using matrix method for single pump. It is seen that for lower parabolic dip, the tolerable limits of dip parameters correspond to dip depth of 0.25% and dip width of 25% of the respective parameters for ideal step index profile case and agree with the earlier predicted linear dip. However, for upper parabolic dip, one gets higher gain and better flatness at these limits. Even up to 1% of the dip depth for 25% of dip width or 75% of dip width for 0.25% of the dip depth or 0.5% of dip depth and 50% of dip width, one can expect performance as good as that of the ideal one. However, since system designers will be aimed to produce ideal profile, our recommendation is to keep tolerable limits within 0.25% of dip depth and 25% of dip width of respective parameters. But one can accept profile with upper parabolic dip if there is deviation within the above relaxation limits for such dip.
References
More filters

Journal ArticleDOI
08 Aug 2005-Optics Express
TL;DR: An all-optical tunable pulse delay scheme that utilizes the power-dependent variation of the refractive index that accompanies stimulated Raman scattering in an optical fiber to produce controllable delays in ultra-high bandwidth telecommunication systems.
Abstract: We demonstrate an all-optical tunable pulse delay scheme that utilizes the power-dependent variation of the refractive index that accompanies stimulated Raman scattering in an optical fiber. Using this technique, we delay 430-fs pulses by up to 85% of a pulse width. The ability to accommodate the bandwidth of pulses shorter than 1 ps in a fiber-based system makes this technique potentially viable for producing controllable delays in ultra-high bandwidth telecommunication systems.

334 citations


Book
01 Jan 2005-
Abstract: Introduction Stimulated Raman Scattering in Optical Fibers Raman Pumping in Optical Fiber Communications Distributed Raman amplification along the transmission span Discrete Raman amplifiers Impairments and Limitations to Raman Amplification.

282 citations


Journal ArticleDOI
Abstract: We experimentally demonstrate the seamless integration of an 8/spl times/2.5 Gb/s wavelength-division-multiplexing passive optical network and radio-over-fiber access system using all-optical up-conversion based on Raman-assisted four-wave mixing in a high-nonlinear fiber. Dispersion-limited reach is extended to >20 km through vestigial-sideband filtering.

117 citations


Journal ArticleDOI
Abstract: In this letter, we present a technique for calculating the Raman gain spectra of germanosilicate fibers from their index profiles. The gain spectra depend on radial profiles of the guided optical modes and the glass composition, in particular the distribution of Si-O-Si and Ge-O-Si bridging bonds. We have obtained spectral coefficients, which represent the contributions from these bonds using Raman gain measurements made on a set of calibration fibers with well-characterized index profiles. We describe how these spectral coefficients can be used in the design of Raman gain fibers, and we demonstrate the accuracy of our technique over a broad range of fiber types.

101 citations


Journal ArticleDOI
Abstract: A scalar multilayer approximation method for calculating the impulse response of multimode optical fibers from measured refractive-index profiles is described. A comparison is made between shapes of measured pulses and calculated pulses.

75 citations


"Effect of lower and upper parabolic..." refers background in this paper

  • ...ai is the boundary of discontinuity at r 1⁄4 ai.(25) In the multilayer approximation, small step size is needed to obtain the profile perfection....

    [...]