Optoelectronics Research Centre, University of Southampton, Southampton, SO17 1BJ, UK.
Opt Lett. 2011 Jun 1;36(11):2050-2. doi: 10.1364/OL.36.002050.
We report a tunable synchronously pumped fiber Raman laser (SPFRL) in the near-infrared (NIR) and visible wavebands pumped by a pulsed, all-fiber PM 1060 nm master oscillator power amplifier (MOPA) and its frequency-doubled output, respectively. The seed was adaptively shaped to deliver rectangular output pulses, thereby enabling selective excitation of individual Raman Stokes lines. Using filtered synchronous feedback of the desired Raman Stokes line, the linewidth of the SPFRL was reduced by a factor of 4 and the extinction ratio of the desired Raman Stokes was improved by more than 3 dB relative to a simple single-pass conversion scheme. A continuous tuning range of 2.2 THz was obtained for each of the Raman Stokes orders in the visible (spanning from green to orange-first to fifth Stokes lines). A larger 5.0 THz tunable range was achieved in the NIR spectral region.
我们报告了一种可调谐的近红外（NIR）和可见波段的同步抽运光纤拉曼激光器（SPFRL），分别由脉冲、全光纤 PM 1060nm 主振荡器功率放大器（MOPA）及其倍频输出泵浦。种子经过自适应整形以提供矩形输出脉冲，从而能够选择性地激发单个拉曼斯托克斯线。通过对所需拉曼斯托克斯线的滤波同步反馈，与简单的单通转换方案相比，SPFRL 的线宽减小了 4 倍，所需拉曼斯托克斯的消光比提高了 3dB 以上。在可见波段（从绿光到橙光第一到第五斯托克斯线）的每个拉曼斯托克斯级都获得了 2.2THz 的连续调谐范围。在 NIR 光谱区域实现了更大的 5.0THz 可调谐范围。
