Performance analysis of optical buffering based on stimulated-Brillouin-scattering-induced acoustic excitation in an optical fiber

We investigate theoretically the buffering performance of an acoustic-excitation-based buffer by stimulated Brillouin scattering in an optical fiber. Firstly, the operation principle and the theoretical model of the buffer are presented. Then, buffering performance including maximum buffering time, bandwidth, retrieval-to-residual energy ratio, readout efficiency, storage density and storage capacity are analyzed in detail, which indicates that a single-mode As2Se3 fiber is a favorable candidate for the storage fiber due to its several prominent merits over a standard single-mode silica fiber. Finally, the buffering performance utilizing both non-chirp and chirp control pulses are simulated, together with the buffering of both NRZ-OOK and RZ-DPSK bit streams in a 0.5 m-long As2Se3 fiber. The results show that the control pulse with a large chirp can greatly improve the retrieval-to-residual energy ratio and the readout efficiency, and this acoustic-excitation-based optical buffer can be used for buffering a bit stream employing either an on-off keying modulation format or a differential phase-shift keying one. (C) 2012 Elsevier B.V. All rights reserved.