非线性光学晶体LBO位相匹配高功率绿光激光器

目的 对非线性光学晶体LBO的倍频属性以及影响倍频效率的各种因素进行理论分析与实验研究。方法 光与物质相互作用的耦合波方程和非线性光学晶体倍频时满足的相位匹配条件。结果 在激光二极管双端泵浦Nd：YVO4腔内倍频绿光激光器的实验中，对于两种不同匹配方式倍频的LBO晶体的倍频特性进行了研究。采用I-类角度位相匹配晶体倍频时，抽运光功率约为26W时，获得了最大输出为4．2W的稳定基模绿光，光．光转换效率达到18％；采用I-类非临界位相匹配晶体倍频时，抽运光功率约为28．9W时，获得了8W稳定的基模绿光输出，光．光转换效率达到31％。结论 通过对于LBO晶体倍频特性的理论分析与实验研究，使Nd：YVO4／LBO激光器获得了较高的输出功率和具有较高的转换效率。     

也谈内腔倍频激光器中非线性晶体长度的选择

本文从非线性光学二次谐波理论出发,考察了基频光两次通过倍频晶体的情况,推导出连驼转内腔倍频激光器的倍频效率公式。     

由内腔倍频直接获取高功率皮秒准单脉冲

描述采用ＢＢＯ非线性晶体,在被动锁模共焦非稳腔Ｎｄ：ＹＡＰ脉冲激光器中实现高效腔内倍频,倍频能量转换效率为８０％。     

基于LBO晶体三倍频的激光实验系统的研究

首先简述了晶体的倍频理论,总结了适用于紫外倍频的非线性光学晶体的特性,提出了倍频晶体选择的理论依据,选用KTP晶体,调试出高效腔外倍频绿光激光器。选用LBO晶体,设计出一台紫外激光器,获得稳定的24.3mw的355nm紫外激光输出,转换效率为10.6%。     

KTP和BBO晶体对1.06μm皮秒光脉冲的倍频效率

用５ｍｍ的ＫＴＰ（ＫＴｉＯＰＯ４）和ＢＢＯ（β－ＢａＢ２Ｏ４）非线性晶体，对皮秒的ＣＰＭ，Ｎｄ∶ＹＡＧ脉冲激光的腔外倍频效应进行研究，获得倍频能量转换效率分别为４２％和３２％，证明ＫＴＰ倍频效率高于ＢＢＯ，结果与理论分析相符．     

LD泵浦KTP腔内倍频Nd:YAG红光激光器

本文报道了二极管端面泵浦Nd:YAG晶体连续660 nm红光激光器的理论设计和试验结果.本实验采用Ⅱ类临界相位匹配KTP晶体对1 319 nm基频波腔内倍频,在泵浦功率7 W时得到86 mW 660 nm红光,光-光转换效率为1.22%.     

BBO晶体相位匹配允许角对倍频效率的影响

根据实验参数，理论计算了ＢＢＯ晶体相位匹配允许角Δθ，其停为毫弧度量级，因此，发散角为毫弧度的激光束通过ＢＢＯ晶体会引起一定的相位失配，降低了倍频转换效率，为此，设计了共焦非稳腔Ｎｄ：ＹＡＰ锁模激光器，近似理想的平面波在ＢＢＯ晶体中实现完全相位匹配，获得了８１％的高效倍频能量转换效率。     

超短脉冲3次谐波转换研究

针对由三阶非线性效应引起的I类角度失谐3次谐波转换进行了研究,讨论了群速度失配、自相位调制和交叉相位调制、晶体厚度以及失谐角度对3倍频光脉冲波形、频谱及转换效率的影响.研究结果表明:群速度延迟使转换效率下降,3倍频光脉冲展宽;自相位调制及交叉相位调制会降低转换效率,使3倍频光脉冲形状发生畸变;晶体厚度对3倍频光脉冲的展宽和转换效率均有较大影响;合适的失谐角度可有效地提高转换效率.     

连续锁模腔内双通倍频Nd：YAG激光器实验研究

报道了２００ＭＨｚ连续主动锁模腔内双通倍频Ｎｄ：ＹＡＧ激光器的实验研究结果。讨论了影响连续锁模激光器二倍频转换效率的主要因素，成功地实现了线型腔双通倍频高效率激光振荡。在输入电功率３．２ｋＷ时，获得了１Ｗ的完全连续锁模倍频基模绿光输出。     

腔内倍频Nd:YAG激光器的研究

运用非线性光学理论,给出了腔内倍频的速率方程,对其进行数值计算,结果表明倍频晶体有一最佳厚度,此时输出的二次谐波功率最大,以优化的腔参数进行实验,获得了输出功率为８Ｗ的蓝绿光。     

偏心度对方形倍频晶体温度场的影响

为了解决非均匀温升对非线性晶体倍频转换效率影响的问题，建立了方形非线性晶体模型．该模型在建立中考虑了基频光具有高斯分布，方形倍频晶体具有周边恒温、端面满足近似绝热等特点．根据非线性晶体腔内倍频的实际需要，给出了方形非线性晶体基频光辐射偏心度的定义，并利用热传导方程，得到了方形非线性晶体受基波偏心辐射时温度场分布的一般解析表达式，解决了在温场模式研究中将倍频使用的方形晶体近似为圆柱形晶体所带来的问题．实验结果表明；当基频光辐射偏心度增大到0．75时，倍频晶体的最高温升下降了21．1％．     

Linear and nonlinear optical spectroscopy of a strongly coupled microdisk-quantum dot system

Cavity quantum electrodynamics, the study of coherent quantum interactions between the electromagnetic field and matter inside a resonator, has received attention as both a test bed for ideas in quantum mechanics and a building block for applications in the field of quantum information processing. The canonical experimental system studied in the optical domain is a single alkali atom coupled to a high-finesse Fabry-Perot cavity. Progress made in this system has recently been complemented by research involving trapped ions, chip-based microtoroid cavities, integrated microcavity-atom-chips, nanocrystalline quantum dots coupled to microsphere cavities, and semiconductor quantum dots embedded in micropillars, photonic crystals and microdisks. The last system has been of particular interest owing to its relative simplicity and scalability. Here we use a fibre taper waveguide to perform direct optical spectroscopy of a system consisting of a quantum dot embedded in a microdisk. In contrast to earlier work with semiconductor systems, which has focused on photoluminescence measurements, we excite the system through the photonic (light) channel rather than the excitonic (matter) channel. Strong coupling, the regime of coherent quantum interactions, is demonstrated through observation of vacuum Rabi splitting in the transmitted and reflected signals from the cavity. The fibre coupling method also allows us to examine the system's steady-state nonlinear properties, where we see a saturation of the cavity-quantum dot response for less than one intracavity photon. The excitation of the cavity-quantum dot system through a fibre optic waveguide is central to applications such as high-efficiency single photon sources, and to more fundamental studies of the quantum character of the system.     

激光二极管端泵Nd:YVO4内腔KTP倍频激光器研究

通过对简单折叠腔进行传输矩阵分析和数值计算,筛选出一组能实现低阈值、高功率、稳定性好的腔参数。当泵浦功率为20.4W时,获得了TEM     

Diode pumped Nd: YVO_4 laser at 671 nm with a type-Ⅱ noncritical phase-matched LBO

A diode pumped intracavity frequency-doubled Nd: YVO4 laser emitting at 671 nm with a type- n noncritical phase-matched LBO crystal is reported. A maximum output power at 671 nm of 404 mW was obtained under an incident pump power of 5.16 W, with an optical-to-optical conversion efficiency up to 7.8%. The output power fluctuates less than 5% while the temperature change of the LBO crystal is maintained at ±0.5℃ at the phase-matched temperature.     

Diode pumped Nd: YVO4 laser at 671 nm with a type-II noncritical phase-matched LBO

A diode pumped intracavity frequency-doubled Nd: YVO₄ laser emitting at 671 nm with a type-II noncritical phase-matched LBO crystal is reported. A maximum output power at 671 nm of 404 mW was obtained under an incident pump power of 5.16 W, with an optical-to-optical conversion efficiency up to 7.8%. The output power fluctuates less than 5% while the temperature change of the LBO crystal is maintained at ± 0.5 °C at the phase-matched temperature.     

在瞬态载荷作用下地下结构非线性动力反应分析

针对实际下工程中普遍存在的的材料非线性以及半无限介质域的处理问题，给出了基于时间有关基本解的时域边界元法与非线性动力有限元法的耦合方法，将该耦合法推广到计及材料非线性的地下结构与周围介质动力相互作用的研究领域。     

热弹性非线性耦合理论及一个半空间问题的解

指出热弹性理论中温度与应变耦合项的非线性性质及其重要性,建议以非耦合理论或线性耦合理论的解为基础,选取适当广义坐标,用变分方法求解非线性耦合问题。对于边界受温度冲击作用的半空间问题,本文计算结果表明,在较高的温度冲击幅度下,非线性耦合理论与线性耦合理论和非耦合理论的差异是不容忽视的。     

锥形飞秒强激光等离子体中Compton散射的能量转换

应用相对论性电子与多光子集团非弹性碰撞模型和经典相对论电动力学理论,分析、计算了锥形飞秒强激光等离子体中多光子非线性Compton散射的能量转换.发现等离子体中的耦合激光场会引起能量转换效率的振荡,而静电场会降低能量转换效率.当高能电子与光子发生双光子非线性Compton散射时,电子能获得最大的能量转换效率.