Rayleigh backscattering: a method to highly compress laser linewidth  

作　　者：Tao Zhu Shihong Huang Leilei Shi Wei Huang Min Liu Kinseng Chiang 

机构地区：[1]Key Laboratory of Optoelectronic Technology and Systems (Ministry of Education), Chongqing University [2]Department of Electronic Engineering, City University of Hong Kong

出　　处：《Chinese Science Bulletin》2014年第33期4631-4636,共6页

基　　金：supported by the National Natural Science Foundation of China(61377066);the Fundamental Research Funds for the Central Universities(CDJZR12125502,106112013CDJZR120002,and 106112013CDJZR160006)

摘　　要：Ultra-narrow linewidth laser with several hundred hertz at room temperature has attracted a great deal of attention in recent years and played a critical role in both optical sensing and communication fields. In this paper, a new method based on Rayleigh backscattering to highly compress the laser linewidth was proposed and demonstrated theoretically and experimentally. By theoretical analysis and simulation, Rayleigh backscattering can be collected in any waveguide structure and all wave bands,which could have a revolutionary impact on the field of laser. A single-longitudinal mode fiber ring laser with130-Hz linewidth was achieved with self-injection feedback structure at normal atmospheric temperature. The linewidth compression based on Rayleigh backscattering lies in the fact that laser linewidth after scattering is narrower than that of incident light in high Rayleigh scattering structure. The self-rejection feedback method expanding free spectra range of laser cavity simultaneously was used to further suppress the mode-hopping and stabilizing output. Experimental results showed that the laser linewidth can be easily narrowed to hundreds of hertz with side-mode suppression up to 75 dB. This agrees with the theoretical analysis and simulation results qualitatively.Ultra-narrow linewidth laser with several hun- dred hertz at room temperature has attracted a great deal of attention in recent years and played a critical role in both optical sensing and communication fields. In this paper, a new method based on Rayleigh backscattering to highly compress the laser linewidth was proposed and demon- strated theoretically and experimentally. By theoretical analysis and simulation, Rayleigh backscattering can be collected in any waveguide structure and all wave bands, which could have a revolutionary impact on the field of laser. A single-longitudinal mode fiber ring laser with 130-Hz linewidth was achieved with self-injection feed- back structure at normal atmospheric temperature. The linewidth compression based on Rayleigh backscattering lies in the fact that laser linewidth after scattering is narrower than that of incident light in high Rayleigh scattering structure. The self-rejection feedback method expanding free spectra range of laser cavity simultaneously was used to further suppress the mode-hopping and stabilizing output. Experimental results showed that the laser linewidth can be easily narrowed to hundreds of hertz with side-mode suppression up to 75 dB. This agrees with the theoretical analysis and simulation results qualitatively.

关 键 词：激光线宽 瑞利散射 线宽压缩 波导结构 自由光谱范围 仿真结果 窄线宽激光 光学传感 

分 类 号：TN248[电子电信—物理电子学]