Martinez Amos, Yamashita Shinji
Department of Electronic Engineering, The University of Tokyo, Tokyo, Japan.
Opt Express. 2011 Mar 28;19(7):6155-63. doi: 10.1364/OE.19.006155.
There is an increasing demand for all-fiber passively mode-locked lasers with pulse repetition rates in the order of gigahertz for their potential applications in fields such as telecommunications and metrology. However, conventional mode-locked fiber lasers typically operate at fundamental repetition rates of only a few megahertz. In this paper, we report all-fiber laser operation with fundamental repetition rates of 4.24 GHz, 9.63 GHz and 19.45 GHz. This is, to date and to the best of our knowledge, the highest fundamental repetition rate reported for an all-fiber laser. The laser operation is based on the passive modelocking of a miniature all-fiber Fabry-Pérot laser (FFPL) by a carbon nanotube (CNT) saturable absorber. The key components for such device are a very high-gain Er:Yb phosphosilicate fiber and a fiber compatible saturable absorber with very small foot print and very low losses. The laser output of the three lasers was close to transform-limited with a pulsewidth of approximately 1 ps and low noise. As a demonstration of potential future applications for this laser, we also demonstrated supercontinuum generation with a longitudinal mode-spacing of 0.08 nm by launching the laser operating at 9.63 GHz into 30 m of a highly nonlinear dispersion shifted fiber.
对于脉冲重复率在千兆赫兹量级的全光纤被动锁模激光器，由于其在电信和计量学等领域的潜在应用，需求日益增长。然而，传统的锁模光纤激光器通常仅在几兆赫兹的基频重复率下工作。在本文中，我们报道了基频重复率分别为4.24 GHz、9.63 GHz和19.45 GHz的全光纤激光器运行情况。据我们所知，这是迄今为止报道的全光纤激光器的最高基频重复率。该激光器运行基于碳纳米管（CNT）可饱和吸收体对微型全光纤法布里 - 珀罗激光器（FFPL）的被动锁模。这种器件的关键组件是增益非常高的铒镱磷硅酸盐光纤和具有非常小尺寸和极低损耗的光纤兼容可饱和吸收体。这三台激光器的输出接近变换极限，脉宽约为1 ps且噪声较低。作为该激光器潜在未来应用的一个演示，我们还通过将工作在9.63 GHz的激光器注入30 m高非线性色散位移光纤，展示了纵向模式间距为0.08 nm的超连续谱产生。
