Tunable All-Optical Delays via Brillouin Slow Light in an Optical Fiber

TLDR

The study demonstrates a technique for generating tunable all‑optical delays in room‑temperature single‑mode optical fibers at telecom wavelengths via stimulated Brillouin scattering. The method exploits the rapid refractive‑index change near the Brillouin gain peak in the fiber. The technique yields delays tunable up to 25 ns by adjusting pump intensity, with the delay wavelength set by the pump wavelength, and works for pulses as short as 15 ns, marking a first step toward telecom buffering.

Abstract

We demonstrate a technique for generating tunable all-optical delays in room temperature single-mode optical fibers at telecommunication wavelengths using the stimulated Brillouin scattering process. This technique makes use of the rapid variation of the refractive index that occurs in the vicinity of the Brillouin gain feature. The wavelength at which the induced delay occurs is broadly tunable by controlling the wavelength of the laser pumping the process, and the magnitude of the delay can be tuned continuously by as much as 25 ns by adjusting the intensity of the pump field. The technique can be applied to pulses as short as 15 ns. This scheme represents an important first step towards implementing slow-light techniques for various applications including buffering in telecommunication systems.