High-Power Low-Noise Fiber Brillouin Amplifier for Tunable Slow-Light Delay Buffer

A high-power low-noise fiber Brillouin amplifier (FBA) has been demonstrated for slow-light delay buffer. Its features including gain, gain saturation, and noise figure (NF), have been characterized. Among them, the gain saturation is highlighted because it is a fundamental limitation for FBA-based slow-light buffer. It is testified that the gain saturation is more easily achieved for lower signal-to-pump ratio (SPR), and the NF is reduced at higher pump level when below Brillouin threshold. The experiment demonstrated that up to 20-ns delay enhancement could be obtained in this high-power FBA for a -30-dBm input signal, as well as with low NF. Besides, the analysis on how the performance of the high power FBA affects the slow-light delay buffer has been presented.