啁啾光纤布拉格光栅展宽器的设计与制作

为获得较大展宽量的光纤器件,在相位掩模版刻写技术的基础上设计并制作了两种啁啾光纤布拉格光栅(CFBG)展宽器。基于相位掩模版刻写技术的原理和CFBG的色散补偿理论,提出了两种展宽器的制作方法,并优化了刻写光路,获得了高反射率、大反射带宽的CFBG。通过拉力传感器控制CFBG的反射谐振波长,通过改进刻写方式制作了大色散量的CFBG级联展宽器和大反射带宽的CFBG串联展宽器。搭建了两种展宽器的测试光源,通过直接测量的方式得到CFBG级联展宽器所提供的展宽量约为345 ps,这与理论结果相符;通过正、反接的方式间接推算了CFBG串联展宽器所提供的展宽量约为278.7 ps,这小于理论结果。     

Influence of optical nonlinearity on combining efficiency in ultrashort pulse fiber laser coherent combining system

The influence of optical nonlinearity on combining efficiency in ultrashort pulse fiber laser coherent combining system is investigated theoretically and experimentally. In the theoretical work, a new theoretical algorithm is presented for the coherent combining efficiency, which can be used to quantify the spectral coherence decay induced by optical nonlinearity imbalance between the sub-beams. The spectral information of the sub-beam is obtained by numerically solving the nonlinear Schrödinger equation (NLSE) in this algorithm to ensure an accurate prediction. In the experimental work, the coherent combining of two all-fiber picosecond lasers is achieved, and the influence of imbalanced optical nonlinearity on the combining efficiency is studied, which agrees with the theoretical prediction. This paper reveals the physical mechanism for the influence of optical nonlinearity on the combining efficiency, which is valuable for the coherent combining of ultrashort pulse fiber laser beams.     

谈谈化学实验室的改建和科学管理

化学实验室是实现实验教学,全面完成化学教学任务的必不可少的基地,如何创造一个良好的基地,一是新建实验教学楼,二是在原有实验室的基础上,进行改造和扩充。无疑前者的办法需要花钱多,时间较长,见效则较迟。后一种办法比较适合大部分学校的实际,我们学校就是按第二种办法来改造和扩充实验室的,本文专谈我校化学实验室的改造、扩充和科学管理。     

尺寸恢复胶的研制

<正> 前言尺寸恢复胶用于机械、零件磨损部位的修复,主要是由合成胶粘剂与固体润滑剂、金属粉状填料组成的,它与金属基材粘结力强,在金属表面形成坚固的抗摩擦涂层,具有低的摩擦系数与较优良的耐磨损性能。聚合物抗摩擦涂层是在固体润滑粘结膜的基础上发展起来的。20世纪40年代美国颁     

An All-Fiberized Chirped Pulse Amplification System Based on Chirped Fiber Bragg Grating Stretcher and Compressor

We report an all-fiberized chirped pulse amplification system without any bulk devices. The stretcher and compressor are chirped fiber Bragg gratings inscribed in a 6/125 μm single-mode fiber and a 30/250 μm largemode-area fiber. The fabrication system of chirped fiber Bragg gratings was designed and built by ourselves. The width of the linear exposure spot was controlled according to the different fiber sizes to improve the fabrication quality, and the parameters of chirped fiber Bragg gratings...     

The 266-nm ultraviolet-beam generation of all-fiberized super-large-mode-area narrow-linewidth nanosecond amplifier with tunable pulse width and repetition rate

We report on a compact, stable, all-fiberized narrow-linewidth (0.045 nm) pulsed laser source emitting laser beam with a wavelength of 266 nm, and tunable pulse width and repetition rate. The system is based on all-fiberized nanosecond amplifier architecture, which consists of Yb-doped fiber preamplifiers and a super-large-mode-area Yb-doped fiber power amplifier. The fiber amplifier with a core of 50 μ is used to raise the threshold of the stimulated Brillouin scattering (SBS) effect and to obtain high output power and single pulse energy. Using lithium triborate (LBO) crystal and beta-barium borate (BBO) crystal for realizing the second-harmonic generation (SHG) and fourth-harmonic generation (FHG), we achieve 17 μJ (1.73 W) and 0.66 μJ (66 mW), respectively, at wavelengths of 532 nm and 266 nm and a repetition rate of 100 kHz with pulse width of 4 ns. This source has great potential applications in fluorescence research and solar-blind ultraviolet optical communication.