25 GHz bandwidth Brillouin slow light in optical fibers

Broadband slow light is demonstrated by using stimulated Brillouin scattering in optical fibers based on a double Brillouin pump, the peaks of which are spectrally separated by twice the Brillouin frequency. The loss spectrum generated by one of the pump waves is fully compensated by the gain spectrum of the other one, which permits the enlargement of the bandwidth to 25 GHz and a variable time delay of up to 10.9 ps with 37 ps pulses.