Long-term storage of a soliton bit stream using phase-sensitive amplification: effects of soliton-soliton interactions and quantum noise

We analyze the long-term stability properties of a soliton bit stream stored in a fiber ring in which linear loss is compensated by phase-sensitive amplification. The analysis and numerical computations presented here model the effects of soliton-soliton interactions, pulse timing and amplitude fluctuations induced by quantum noise, and phase noise caused by guided acoustic-wave Brillouin scattering. We show that phase-sensitive amplification significantly enhances the storage ring's stability properties, so that the one's (the soliton pulses) are asymptotically stable and that the noise on the zero's of the bit stream (i.e., where solitons are absent) is bounded. The soliton-soliton interactions and noise-induced pulse timing jitter are substantially reduced by phase-sensitive amplification. Finally, we demonstrate that by adding a relatively small amount of modulation to the pump pulses that drive the amplifiers, it is possible to eliminate all of the residual pulse interactions and timing jitter. Published by Elsevier Science B.V. All rights reserved.