Low-noise and high-gain Brillouin optical amplifier for narrowband active optical filtering based on a pump-to-signal optoelectronic tracking

Abstract

We implement and characterize an optical narrowband amplifier based on stimulated Brillouin scattering with pump-to-signal relative frequency fluctuations overcome thanks to an active pump tracking. We achieve a precise characterization of this amplifier in terms of gain and noise degradation (noise figure). The performances of this stable selective amplification are compared to those of a conventional erbium-doped fiber amplifier in order to highlight the interest of the Brillouin amplification solution for active narrow optical filtering with a bandpass of 10 MHz. Thanks to the simple optoelectronic pump-to-signal tracking, the Brillouin active filter appears as a stable and reliable solution for narrowband optical processing in the coherent optical communication context and optical sensor applications.

Weak laser pulse signal amplification based on a fiber Brillouin amplifier

“…Stimulated Brillouin scattering (SBS) is a relatively simple and efficient mechanism for weak optical signal amplification with a high gain and high signal-to-noise ratio (SNR). According to various references, the results show the possibility of using a Brillouin amplifier to enhance weak signals [17][18][19][20] . About a 2 × 10 9 signal amplification factor was achieved for an input signal of 1 pJ [17] .…”

“…Image amplification by a factor of 300 was demonstrated with Brillouin two-beam coupling in CS 2 [19] . With a pump power at the threshold, the Brillouin amplifier can provide a very high gain: a gain of 45 dB was obtained with 8 dBm of pump power in a 25 km single mode fiber (SMF) for a −45 dBm input power signal [20] . Those experiments involved a high pump power density to amplify the Stokes pulse.…”

Resonantly enhanced nonreciprocal silicon Brillouin amplifier

“…Once entirely absent from silicon photonics, these Brillouin interactions have emerged as one of the strongest and most tailorable nonlinearities in silicon [16,17], opening the door to net optical amplification [18][19][20] and Brillouin lasing in silicon photonic circuits [21]. While recent demonstrations have achieved 2-5 dB of amplification [19,20], scaling the degree of amplification to levels necessary for high-fidelity filtering [22][23][24][25] and small-signal detection schemes [26] remains a nontrivial challenge [27].…”

Combining fiber Brillouin amplification with a repeater laser station for fiber-based optical frequency dissemination over 1400 km

“…Fiber Brillouin amplifiers (FBAs) excel due to the narrow amplification bandwidth of ≈10 MHz and a gain of up to 50 dB [28]. As a result of the propagation direction sensitive gain and the saturation of the Brillouin gain with input power [28,30] beat signals obtained on FBA-based links have a high amplitude stability. Therefore, low CS rates are achievable.…”

“…However, two limitations are apparent that may prevent similar performance for even longer distances. First, FBA-based fiber links are subject to spontaneous Brillouin backscattering background [30,40]. For the average distance of ≈200 km between available installation points for the in-field FBA modules (FBAMs) on the fiber loop PTB-UoS-PTB, optical power at the input of the amplifier is only ≈100 nW.…”