Investigation on competition between the input signal and noise in a Brillouin amplifier

We theoretically and experimentally investigate the competition mechanism between the input signal and noise in a Brillouin amplifier, and the influence of the delay time of the pump pulse relative to the signal pulse on this competition. Results show that as the input signal intensity increases, the amplified Brillouin scattering (ABS) noise gradually weakens, while the signal amplification predominates. When the ratio of the input signal to the pump intensity is greater than 10⁻⁴, the ABS noise will be almost completely suppressed. The delay time should be controlled as the pump pulse half-width to achieve high signal-noise-ratio and high amplification.