Observation of pulse delaying and advancement in optical fibers using stimulated Brillouin scattering

TLDR

The study aims to use stimulated Brillouin scattering to optically control the group velocity of pulses in optical fibers. The authors derive the basic theory of group‑delay changes and experimentally demonstrate the effect in two conventional fiber types. We experimentally demonstrate that stimulated Brillouin scattering can optically control the group velocity of pulses in optical fibers, achieving 10⁻³ changes in group index over several kilometres and producing tens‑of‑nanosecond delays or advancements, marking the first evidence of such strong optically‑controlled delay changes.

Abstract

We demonstrate experimentally that it is possible to control optically the group velocity of an optical pulse as it travels along an optical fiber. To achieve this control we use the effect of Stimulated Brillouin Scattering. In our experiments we have achieved changes in the group index of 10-3 in several kilometer-length fibers, thus leading to pulse delaying and advancement in the range of tens of nanoseconds. We believe that this is the first evidence of such optically-controlled strong delay changes in optical fibers. In this paper we derive the basic theory behind these group-delay changes and we demonstrate the effect in two kinds of fibers which are conventionally used.