Journal of Lightwave Technology

Broadband SBS Slow Light in an Optical Fiber

Zhaoming Zhu, Andrew M. C. Dawes, Daniel J. Gauthier, Lin Zhang, Alan Eli Willner

Published Jan 1, 2007• 200 citations

Abstract

In this paper, we investigate slow light via stimulated Brillouin scattering (SBS) in a room temperature optical fiber that is pumped by a spectrally broadened laser. Broadening the spectrum of the pump field increases the linewidth Deltaomegapof the Stokes amplifying resonance, thereby increasing the slow-light bandwidth. One physical bandwidth limitation occurs when the linewidth becomes several times larger than the Brillouin frequency shift OmegaBso that the anti-Stokes absorbing resonance substantially cancels out the Stokes amplifying resonance and, hence, the slow-light effect. We find that partial overlap of the Stokes and anti-Stokes resonances can actually lead to an enhancement of the slow-light delay-bandwidth product when Deltaomegapsime1.3OmegaB. Using this general approach, we increase the Brillouin slow-light bandwidth to over 12 GHz from its nominal linewidth of ~30 MHz obtained for monochromatic pumping. We controllably delay 75-ps-long pulses by up to 47 ps and study the data-pattern dependence of the broadband SBS slow-light system

DOI: 10.1109/jlt.2006.887188

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