Slow light with a swept-frequency source

TL;DR

This paper presents a novel method for achieving broadband slow light in optical fibers using a swept-frequency source, demonstrating tunable delays up to 38 ns limited by SBS threshold.

Contribution

It introduces a new concept for SBS-based slow light applicable to frequency-swept sources, enabling delay over the entire fiber transparency window.

Findings

Achieved 10 ns delay at 1550 nm with a 0.4 MHz/ns sweep rate

Maximum delay of approximately 38 ns limited by SBS threshold

Demonstrated broadband slow light with tunable delays

Abstract

We introduce a new concept for stimulated-Brillouin-scattering-based slow light in optical fibers that is applicable for broadly-tunable frequency-swept sources. It allows slow light to be achieved, in principle, over the entire transparency window of the optical fiber. We demonstrate a slow light delay of 10 ns at 1550 nm using a 10-m-long photonic crystal fiber with a source sweep rate of 0.4 MHz/ns and a pump power of 200 mW. We also show that there exists a maximal delay obtainable by this method, which is set by the SBS threshold, independent of sweep rate. For our fiber with optimum length, this maximum delay is ~38 ns, obtained for a pump power of 760 mW.