Mamdoohi G, Soltanian M R K, Légaré F
Opt Express. 2023 Jul 31;31(16):26167-26177. doi: 10.1364/OE.496936.
A simple high flat amplitude multi-wavelength Brillouin-Raman fibre laser (MBRFL) with 10 GHz spacing and excellent optical signal-to-noise ratio (OSNR) in C-Band spectral region is demonstrated. The laser consists of a linear cavity in which 12 km dispersion compensating fiber (DCF) in addition to 49 cm Bismuth-oxide Erbium doped fiber (Bi-EDF) are employed as a gain medium for amplification. The impact of Raman pump power distribution through changes in coupling ratio on amplitude flatness is carried out by comparing the peak power discrepancy between odd- and even-order Brillouin Stoke lines. This is the main property that allows the efficient controlling of gain propagation between lasing lines that is vital for Stokes flattening initiation and other output spectra characteristics. The attainment of MBRFL with outstanding OSNR necessitates the utilizing of Bi-EDF as a noise suppressor. By utilizing a 50/50 coupler, 354 identical channels together with uniform Brillouin Stokes linewidth within only 0.3-dB maximum power difference between adjacent channels is generated. The average OSNR and Stokes power are 28 dB and -5 dBm respectively when the RPP is set at 1300 mW. To date, this is the highest flatness 10 GHz spacing MBRFL with outstanding OSNR attained in MBRFL that incorporate only a single Raman pump unit.
展示了一种简单的高平坦幅度多波长布里渊 - 拉曼光纤激光器（MBRFL），其在C波段光谱区域具有10GHz的间距和出色的光信噪比（OSNR）。该激光器由一个线性腔组成，其中除了49cm的铋氧化物铒掺杂光纤（Bi - EDF）外，还采用了12km的色散补偿光纤（DCF）作为放大的增益介质。通过比较奇数和偶数阶布里渊斯托克斯线之间的峰值功率差异，研究了拉曼泵浦功率分布通过耦合比变化对幅度平坦度的影响。这是有效控制激光线之间增益传播的主要特性，对于斯托克斯平坦化的启动和其他输出光谱特性至关重要。要获得具有出色OSNR的MBRFL，需要使用Bi - EDF作为噪声抑制器。通过使用50/50耦合器，产生了354个相同的通道，相邻通道之间的最大功率差仅为0.3dB，布里渊斯托克斯线宽均匀。当拉曼泵浦功率（RPP）设置为1300mW时，平均OSNR和斯托克斯功率分别为28dB和 - 5dBm。迄今为止，这是在仅包含单个拉曼泵浦单元的MBRFL中获得的具有出色OSNR的最高平坦度10GHz间距的MBRFL。
