排序方式: 共有166条查询结果,搜索用时 421 毫秒
31.
二次谐波产生的非线性相移的解析研究 总被引:5,自引:0,他引:5
给出一种分析二阶非线性级联效应的解析方法,对Ⅱ型二次谐波产生的非线性级联效应进行了详细的理论研究和分析。结果表明倍频晶体中正交输入两个振幅不相等的基波分量时,在近相位匹配下二阶非线性级联效应能够产生大的相移。利用本文的解析方法可以对任意二阶非线性相移产生的过程进行优化,从而以最小的需求输入功率来获得特定的相移。还对由非线性相移诱导的且与光强有关的偏振旋转效应和一种基于偏振旋转效应的全光偏振开关进行了分析和讨论。本文的结果对于建立一种基于Ⅱ型倍频晶体中非线性相移诱导偏振旋转效应的新全固化被动锁模飞秒激光装置具有十分重要的意义。 相似文献
32.
33.
Lasing Characteristics of Tm^3+:Ho^3+ Codoped Silica Fibre Laser Pumped by 1.18-μm Raman Fibre Laser 总被引:1,自引:0,他引:1 下载免费PDF全文
The fundamental characteristics of Fabry-Perot-cavity continuous-wave Tm-Ho codoped silica fibre lasers pumped by a 1.18μm Raman fibre laser are presented. A maximum output power of 930mW at 1880nm is generated for a fibre length of 1 m from the transition of Tm^3 , with a slope efficiency of 32.4%. For a 3-m-long fibre, the maximum output power decreases to 650 mW at 1960 nm due to the laser emission from Ho^3 with a lower slope efficiency of 25%, which clearly shows the effective energy transfer from Tm^3 to Ho^3 . The wavelength redshifting of the laser emission originates from the transition competition and the emission cross section difference between Tm^3 and Ho^3 . 相似文献
34.
35.
通过飞秒放大增益饱和理论及飞秒脉冲展宽的理论计算与分析,指出在优化放大腔结构参数及改变抽运光能量情况下,可以在省略展宽器基础上实现中等能量的飞秒脉冲再生放大.以此为依据,采用低抽运能量和放大腔中钛宝石晶体离焦技术,成功地进行了无展宽器的高重复率飞秒钛宝石再生放大及压缩技术的实验研究,并获得了高光束质量的飞秒放大光脉冲,放大光脉冲能量大于100μJ,重复频率为1kHz,光谱带宽7.7nm,压缩后脉宽500fs.
关键词:
飞秒光脉冲
再生放大
光束质量
增益饱和 相似文献
36.
Three-dimensional bitwise optical recording with a density of 500 Gb/cm3 in fused silica using a Ti:sapphire femtosecond laser modulated by binary digits is demonstrated. Laser pulses modulation is realized by modulating two circuits of trigger pulses signal which are used to control laser pulses trapping and switching out from cavity, respectively. Bits are optically readout in both a parallel reading (phase-contrast) and a serial reading (confocal-type) methods. The method for modulating laser pulses can also be used in all of pulsed laser systems which operate in cavity-dumping configuration. 相似文献
37.
38.
The writing of an internal diffraction grating in optical glass plate is demonstrated using low-density plasmaformation excited by a high-intensity femtosecond Ti:sapphire laser.The same diffraction efficiency at±1,±2,and 0 order is achieved by multiple layers writing.The dependences of diffractive efficiencyon the irradiated energy,the speed of writing,the numerical aperture(NA)of the focusing objective,and materials are investigated in detail.The grating is birefringent.It is attributed to residual stressinteraction between glass and femtosecond laser pulse. 相似文献
39.
双泵浦光子晶体光纤参量放大研究 总被引:6,自引:5,他引:1
利用光子晶体光纤在不同零色散波长附近具有不同色散的特性,研究了在零色散波长为780 nm和1550 nm附近的双泵浦光子晶体光纤参量放大过程.在780 nm附近,讨论了零色散波长变化对双泵浦光子晶体光纤参量放大的影响.数值模拟结果表明:当零色散波长发生微小的变化时,信号增益谱带宽会发生很大的变化.当两泵浦光之间的波长差值减小时,零色散波长的变化对参量放大的影响在很大程度上可以得到抑制,但是增益带宽会有一定的减小.依据这一原理,在1550 nm附近设计光子晶体光纤中的色散平坦光纤参量放大,在5 m长的光子晶体光纤中,当峰值功率为10 W时,得到了增益为65 dB,带宽达到420 nm且极为平坦的增益谱. 相似文献
40.