【作者】 张会云；

【导师】 王涛； 姚建铨；

【作者基本信息】 天津大学 ， 光电子技术， 2007， 博士

【摘要】 全固态激光器是一种优良的新型光源,因具有效率高、结构紧凑、输出稳定、寿命长等优点,在工业、科研、军事等领域发挥着越来越大的作用,已成为应用激光器中的主流。高功率的全固态绿光、红光激光器在激光彩色显示、激光医疗、高密度光存储、材料处理和分析、超高清晰度打印和扫描等领域有着非常广泛的应用前景,是近年来全固态激光技术研究的热点。近年来,介电常数和磁导率同时或只有一个为负数的新型人工材料——特异材料,己经在微波段乃至近红外通过人工合成实现。人们通过将特异材料引入一维光子晶体中,发现了新型的光子带隙。由于这些光子带隙具有与传统的布拉格带隙截然不同的性质,并具有潜在的应用前景,因此含有特异材料的一维光子晶体已成为了当前的一个研究热点。本文的主要创新点可以归纳如下:1、采用两个150W半导体侧泵模块,进行了单棒和双棒串接声光调Q内腔倍频绿光激光器的研究。采用一个150W模块进行内腔倍频声光调Q绿光激光器实验研究,用KTP内腔倍频,得到76.9W的绿光输出,光-光转换效率11.6%;用LBO倍频得到79.3W的绿光输出。采用两个150泵浦组件串接,双声光调Q,高抗灰迹KTP晶体倍频得到131W的绿光激光输出,光-光转换效率13.1%,在激光器输出功率为128W时功率不稳定度为0.71%,光束质量因子M2在80W时为6.7。此结果在目前国内外高功率绿光激光器光束质量和稳定性方面处于领先水平。在此基础上我们研制了120W绿光激光器样机,用于前列腺治疗仪的研究和开发。2、分别采用50W和150W半导体侧泵模块、采用侧面泵浦方式和优化的三镜折叠谐振腔设计,Ⅱ类相位匹配KTP晶体作为腔内倍频晶体进行了高功率连续绿光激光器的实验研究。用50W型泵浦组件,得到18.7W的连续波绿光激光输出,对应的光-光转换效率为10.4%,功率不稳定度为0.4031%,在以上实验结果的基础上,我们研制出国产化的全固态10W连续绿光激光器实用化样机。采用单个150W模块泵浦,实现了输出功率51.2W的连续绿光激光输出,对应的光-光转换效率为10.3%,在输出功率为47.4W时测得激光功率不稳定度为0.49%,用刀口法测量了激光光束质量,M2小于9。据我们所知,在采用棒状工作物质的全固态连续绿光激光器中,该输出功率达到国际领先水平。3、进行了高功率连续红光激光器的实验研究。使用Nd:YVO4和LBO晶体进行了LD单端泵浦Nd:YVO4/LBO连续红光激光器的实验研究,当泵浦功率为24.56 W时,获得了671 nm激光功率1.203 W,光-光转换效率为4.9 %。激光器输出功率为1.08 W时测得激光功率不稳定度为0.52 %。用LD双端泵浦单块Nd:YVO4晶体,腔内LBO倍频,当泵浦功率为36W时,获得671nm CW输出2.33W,光-光转换效率为6.5%,输出功率为2W附近激光功率不稳定度小于0.5%,用M2测试仪测得光束质量为M2=3.6。以上结果在目前国内外高功率连续波全固态红光激光器功率稳定性方面处于领先水平。4、采用转移矩阵方法,分别研究了含两类特异材料的一维光子晶体(对称Fibonacci序列和异质结构)的输运特性。研究了由正、负折射率材料交替生长按对称Fibonacci序列排列形成的一维准周期光子晶体的特殊性质:具有平均折射率为零的光子带隙。将该平均折射率为零的光子带隙与布拉格带隙比较后发现,前者受入射角度和偏振的影响较后者小。这意味着零平均折射率全向能隙可被用来设计带宽固定的小型化全角度反射器。研究了由两类单负材料组成的一维异质结构光子晶体透射特性。选择合适的参数,使得一维异质结构光子晶体的平均磁导率和平均介电常数均为零,发现其禁带中出现了一个很窄的共振传播模式,位相延迟为零,这种传播模式不会随着入射角度和偏振的改变而移动,可以用来设计全方向单通道滤波器。研究了在满足零平均磁导率和零平均介电常数的条件下,形成的异质结构光子晶体中引入缺陷时的透射性质。在此结构中,调整缺陷层的数目和厚度得到多通道滤波特性。可以利用这一特性设计出一种全新的基于光子晶体的多通道滤波器。更多还原

【Abstract】 Diode-pumped solid-state lasers (DPSL) have become main-stream of lasers in application due to their many advantages such as high efficiency, compactness, high stability, and long lifetime. They are widely used in the field of industry, scientific research, military etc. During the past few years high-power LD pumped green and red laser have become the focus of research because of their numerous applications such as laser colour display, laser medicine, high-density optical data storage, material processing, high-resolution printing, etc.Recently, metamaterials in which both permittivityεandμare negative or only one of the two parametersεandμis negative have been realized in microwave and near-infrared. When the metamaterials are introduced in one-dimensional photonic crystals, new types of photonic band gaps appear. Since the properties of such photonic band gaps are different from those of the Bragg gap, and they can lead to potential applications, one-dimensional photonic crystals containing metamaterials have become a subject of great interest for optical physics.The main contents and key creation points of this dissertation are as follows:(1) Using two GKPM-150 side-pumped laser modules, we investigated single-rod and double-rod A-O Q-switched intracavity-doubled lasers. Using a single 150W laser module with KTP crystal, we obtained 76.9W green output power with optical-optical conversion efficiency of 11.6%. Using the same module with LBO crystal, we obtained 79.3W green output power with optical-optical conversion efficiency of 18.2%. With two GKPM-150 modules in tandem with each other, double acousto-optic Q-switched and high gray track resistance KTP frequency-doubled, a laser with output power of 131W is achieved, of which the optical-to-optical conversion efficiency is 13.1%, and the power instability is 0.71% at 128W, and the beam transfer factor M2 is measured to be 6.7 at the output power of 80W. This represents, to the best of our knowledge, the advanced level so far in the respect of power stability and the beam transfer factor M2. Based on this experiment, a 120W green laser model have been accomplished which can be applied in treatment of prostate hyperplasia.(2) Using 50W, 150W side-pumped laser modules, we investigated high power continuum wave (CW) green laser with an LD side-pumped configuration and three mirror folded cavity design and KTP ofⅡ-type phase-matching for frequency doubling. Using a 50W module, we obtained 18.7W CW 532nm output power, of which the optical-to-optical conversion efficiency is 10.4%, and the power instability is 0.4031%. A prototype of cw green laser with 10-watt is made out with domestic devices. The main characteristic of it belongs to advanced level in China. Using a 150W module, we obtained 51.2W CW 532nm output power, of which the optical-to-optical conversion efficiency is 10.3%, and the power instability is 0.49%, and the beam transfer factor is measured to be better than 9 measured by knife-edge method. This represents, as far as we know, in traditional laser with rod material, this output power is ahead in the world.(3) Researches on high power continuum wave red laser. The 671nm laser reaches 1.203W when the absorbed pump power is 24.56W, with an optical to optical conversion efficiency of 4.9%. The amplitude noise is 0.52% (rms) in an hour when the output power is at about 1.08W. A double-end-pumped Nd:YVO4/LBO continuous wave laser is also achieved. We obtained 2.33W CW 671nm output power when the total pump power is 36W, of which the optical-to-optical conversion efficiency is 6.5%. The power instability is less than 0.5% at output power of about 2W with M2=3.6. The above mentioned results are ahead in the world at the respect of power stability.(4) By means of the transfer-matrix method, we investigate the transmission properties of one-dimensional (1D) photonic crystals composed of symmetrical Fibonacci sequences and heterostructures containing two kinds of metamaterials, respectively. The two types of metamaterials include negative-index materials (also called double-negative materials or left-handed materials) whose permittivity and permeability are simultaneously negative and single-negative materials whose permeability (permittivity) is negative but permittivity (permeability) is positive. The band structures of symmetrical Fibonacci sequences (SFS) composed of positive and negative refractive index materials are studied with a transfer matrix method. A new type of omni-directional zero-n gaps is found in the SFS. In contrast to the Bragg gaps, such an omni-directional zero- n gap is insensitive to the incident angles and polarization, and is invariant upon the change of the ratio of the thicknesses of two media. It is found that omni-directional zero-n gap exists in all the SFS, and it is rather stable and independence of the structure sequence. The transmission of 1D photonic heterostructures with single negative material was investigated by the transfer matrix theory. With suit parameters, the average permittivity and the average permeability is zero. A complete transmission peak exists in the forbidden gap. They are independent of incident angles and polarizations and have zero phase delay, which can be utilized to design zero-phase-shift omni-directional filters. Transmission studies for multiple heterostructures consisting of two kinds of single-negative materials inserted with defects are presented when the average permittivity and the average permeability is zero. The results show that multiple-channeled filters can be obtained by adjusting the period number m and thicknesses of defects. These structures provide an excellent way to select useful multiple-channeled optical signals from a stop gap, and it is useful in optical device applications.更多还原