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《光电技术》专业英语词汇1.Absorption coefficient 吸收系数2.Acceptance angle 接收角3.fibers 光纤4.Acceptors in semiconductors 半导体接收器5.Acousto-optic modulator 声光调制6.Bragg diffraction 布拉格衍射7.Air disk 艾里斑8.angular radius 角半径9.Airy rings 艾里环10.anisotropy 各向异性11.optical 光学的12.refractive index 各向异性13.Antireflection coating 抗反膜14.Argon-ion laser 氩离子激光器15.Attenuation coefficient 衰减系数16.Avalanche 雪崩17.breakdown voltage 击穿电压18.multiplication factor 倍增因子19.noise 燥声20.Avalanche photodiode(APD) 雪崩二极管21.absorption region in APD APD 吸收区域22.characteristics-table 特性表格23.guard ring 保护环24.internal gain 内增益25.noise 噪声26.photogeneration 光子再生27.primary photocurrent 起始光电流28.principle 原理29.responsivity of InGaAs InGaAs 响应度30.separate absorption and multiplication(SAM) 分离吸收和倍增31.separate absorption grading and multiplication(SAGM) 分离吸收等级和倍增32.silicon 硅33.Average irradiance 平均照度34.Bandgap 带隙35.energy gap 能级带隙36.bandgap diagram 带隙图37.Bandwidth 带宽38.Beam 光束39.Beam splitter cube 立方分束器40.Biaxial crystal双s 轴晶体41.Birefringent 双折射42.Bit rate 位率43.Black body radiation law 黑体辐射法则44.Bloch wave in a crystal 晶体中布洛赫波45.Boundary conditions 边界条件46.Bragg angle 布拉格角度47.Bragg diffraction condition 布拉格衍射条件48.Bragg wavelength 布拉格波长49.Brewster angle 布鲁斯特角50.Brewster window 布鲁斯特窗51.Calcite 霰石52.Carrier confinement 载流子限制53.Centrosymmetric crystals 中心对称晶体54.Chirping 啁啾55.Cladding 覆层56.Coefficient of index grating 指数光栅系数57.Coherence连贯性pensation doping 掺杂补偿59.Conduction band 导带60.Conductivity 导电性61.Confining layers 限制层62.Conjugate image 共轭像63.Cut-off wavelength 截止波长64.Degenerate semiconductor 简并半导体65.Density of states 态密度66.Depletion layer 耗尽层67.Detectivity 探测率68.Dielectric mirrors 介电质镜像69.Diffraction 衍射70.Diffraction g rating 衍射光栅71.Diffraction grating equation 衍射光栅等式72.Diffusion current 扩散电流73.Diffusion flux 扩散流量74.Diffusion Length 扩散长度75.Diode equation 二极管公式76.Diode ideality factor 二极管理想因子77.Direct recombinatio直n接复合78.Dispersion散射79.Dispersive medium 散射介质80.Distributed Bragg reflector 分布布拉格反射器81.Donors in semiconductors 施主离子82.Doppler broadened linewidth 多普勒扩展线宽83.Doppler effect 多普勒效应84.Doppler shift 多普勒位移85.Doppler-heterostructure 多普勒同质结构86.Drift mobility 漂移迁移率87.Drift Velocity 漂移速度88.Effective d ensity o f s tates 有效态密度89.Effective mass 有效质量90.Efficiency 效率91.Einstein coefficients 爱因斯坦系数92.Electrical bandwidth of fibers 光纤电子带宽93.Electromagnetic wave 电磁波94.Electron affinity 电子亲和势95.Electron potential energy in a crystal 晶体电子阱能量96.Electro-optic effects 光电子效应97.Energy band 能量带宽98.Energy band diagram 能量带宽图99.Energy level 能级100.E pitaxial growth 外延生长101.E rbium doped fiber amplifier 掺饵光纤放大器102.Excess carrier distribution 过剩载流子扩散103.External photocurrent 外部光电流104.Extrinsic semiconductors 本征半导体105.Fabry-Perot laser amplifier 法布里-珀罗激光放大器106.Fabry-Perot optical resonator 法布里-珀罗光谐振器107.Faraday effect 法拉第效应108.Fermi-Dirac function 费米狄拉克结109.Fermi energy 费米能级110.Fill factor 填充因子111.Free spectral range 自由谱范围112.Fresnel’s equations 菲涅耳方程113.Fresnel’s optical indicatrix 菲涅耳椭圆球114.Full width at half maximum 半峰宽115.Full width at half power 半功率带宽116.Gaussian beam 高斯光束117.Gaussian dispersion 高斯散射118.Gaussian pulse 高斯脉冲119.Glass perform 玻璃预制棒120.Goos Haenchen phase shift Goos Haenchen 相位移121.Graded index rod lens 梯度折射率棒透镜122.Group delay 群延迟123.Group velocity 群参数124.Half-wave plate retarder 半波延迟器125.Helium-Neon laser 氦氖激光器126.Heterojunction 异质结127.Heterostructure 异质结构128.Hole 空穴129.Hologram 全息图130.Holography 全息照相131.Homojunction 同质结132.Huygens-Fresnel principle 惠更斯-菲涅耳原理133.Impact-ionization 碰撞电离134.Index matching 指数匹配135.Injection 注射136.Instantaneous irradiance 自发辐射137.Integrated optics 集成光路138.Intensity of light 光强139.Intersymbol interference 符号间干扰140.Intrinsic concentration 本征浓度141.Intrinsic semiconductors 本征半导体142.Irradiance 辐射SER 激光144.active medium 活动介质145.active region 活动区域146.amplifiers 放大器147.cleaved-coupled-cavity 解理耦合腔148.distributed Bragg reflection 分布布拉格反射149.distributed feedback 分布反馈150.efficiency of the He-Ne 氦氖效率151.multiple quantum well 多量子阱152.oscillation condition 振荡条件ser diode 激光二极管sing emission 激光发射155.LED 发光二极管156.Lineshape function 线形结157.Linewidth 线宽158.Lithium niobate 铌酸锂159.Load line 负载线160.Loss c oefficient 损耗系数161.Mazh-Zehnder modulator Mazh-Zehnder 型调制器162.Macrobending loss 宏弯损耗163.Magneto-optic effects 磁光效应164.Magneto-optic isolator 磁光隔离165.Magneto-optic modulator 磁光调制166.Majority carriers 多数载流子167.Matrix emitter 矩阵发射168.Maximum acceptance angle 最优接收角169.Maxwell’s wave equation 麦克斯维方程170.Microbending loss 微弯损耗171.Microlaser 微型激光172.Minority carriers 少数载流子173.Modulated directional coupler 调制定向偶合器174.Modulation of light 光调制175.Monochromatic wave 单色光176.Multiplication region 倍增区177.Negative absolute temperature 负温度系数 round-trip optical gain 环路净光增益179.Noise 噪声180.Noncentrosymmetric crystals 非中心对称晶体181.Nondegenerate semiconductors 非简并半异体182.Non-linear optic 非线性光学183.Non-thermal equilibrium 非热平衡184.Normalized frequency 归一化频率185.Normalized index difference 归一化指数差异186.Normalized propagation constant 归一化传播常数187.Normalized thickness 归一化厚度188.Numerical aperture 孔径189.Optic axis 光轴190.Optical activity 光活性191.Optical anisotropy 光各向异性192.Optical bandwidth 光带宽193.Optical cavity 光腔194.Optical divergence 光发散195.Optic fibers 光纤196.Optical fiber amplifier 光纤放大器197.Optical field 光场198.Optical gain 光增益199.Optical indicatrix 光随圆球200.Optical isolater 光隔离器201.Optical Laser amplifiers 激光放大器202.Optical modulators 光调制器203.Optical pumping 光泵浦204.Opticalresonator 光谐振器205.Optical tunneling光学通道206.Optical isotropic 光学各向同性的207.Outside vapor deposition 管外气相淀积208.Penetration depth 渗透深度209.Phase change 相位改变210.Phase condition in lasers 激光相条件211.Phase matching 相位匹配212.Phase matching angle 相位匹配角213.Phase mismatch 相位失配214.Phase modulation 相位调制215.Phase modulator 相位调制器216.Phase of a wave 波相217.Phase velocity 相速218.Phonon 光子219.Photoconductive detector 光导探测器220.Photoconductive gain 光导增益221.Photoconductivity 光导性222.Photocurrent 光电流223.Photodetector 光探测器224.Photodiode 光电二极管225.Photoelastic effect 光弹效应226.Photogeneration 光子再生227.Photon amplification 光子放大228.Photon confinement 光子限制229.Photortansistor 光电三极管230.Photovoltaic devices 光伏器件231.Piezoelectric effect 压电效应232.Planck’s radiation distribution law 普朗克辐射法则233.Pockels cell modulator 普克尔斯调制器234.Pockel coefficients 普克尔斯系数235.Pockels phase modulator 普克尔斯相位调制器236.Polarization 极化237.Polarization transmission matrix 极化传输矩阵238.Population inversion 粒子数反转239.Poynting vector 能流密度向量240.Preform 预制棒241.Propagation constant 传播常数242.Pumping 泵浦243.Pyroelectric detectors 热释电探测器244.Quantum e fficiency 量子效应245.Quantum noise 量子噪声246.Quantum well 量子阱247.Quarter-wave plate retarder 四分之一波长延迟248.Radiant sensitivity 辐射敏感性249.Ramo’s theorem 拉莫定理250.Rate equations 速率方程251.Rayleigh criterion 瑞利条件252.Rayleigh scattering limit 瑞利散射极限253.Real image 实像254.Recombination 复合255.Recombination lifetime 复合寿命256.Reflectance 反射257.Reflection 反射258.Refracted light 折射光259.Refractive index 折射系数260.Resolving power 分辩力261.Response time 响应时间262.Return-to-zero data rate 归零码263.Rise time 上升时间264.Saturation drift velocity 饱和漂移速度265.Scattering 散射266.Second harmonic generation 二阶谐波267.Self-phase modulation 自相位调制268.Sellmeier dispersion equation 色列米尔波散方程式269.Shockley equation 肖克利公式270.Shot noise 肖特基噪声271.Signal to noise ratio 信噪比272.Single frequency lasers 单波长噪声273.Single quantum well 单量子阱274.Snell’s law 斯涅尔定律275.Solar cell 光电池276.Solid state photomultiplier 固态光复用器277.Spectral intensity 谱强度278.Spectral responsivity 光谱响应279.Spontaneous emission 自发辐射280.stimulated emission 受激辐射281.Terrestrial light 陆地光282.Theraml equilibrium 热平衡283.Thermal generation 热再生284.Thermal velocity 热速度285.Thershold concentration 光强阈值286.Threshold current 阈值电流287.Threshold wavelength 阈值波长288.Total acceptance angle 全接受角289.Totla internal reflection 全反射290.Transfer distance 转移距离291.Transit time 渡越时间292.Transmission coefficient 传输系数293.Tramsmittance 传输294.Transverse electric field 电横波场295.Tranverse magnetic field 磁横波场296.Traveling vave lase 行波激光器297.Uniaxial crystals 单轴晶体298.UnPolarized light 非极化光299.Wave 波300.W ave equation 波公式301.Wavefront 波前302.Waveguide 波导303.Wave n umber 波数304.Wave p acket 波包络305.Wavevector 波矢量306.Dark current 暗电流307.Saturation signal 饱和信号量308.Fringing field drift 边缘电场漂移plementary color 补色310.Image lag 残像311.Charge handling capability 操作电荷量312.Luminous quantity 测光量313.Pixel signal interpolating 插值处理314.Field integration 场读出方式315.Vertical CCD 垂直CCD316.Vertical overflow drain 垂直溢出漏极317.Conduction band 导带318.Charge coupled device 电荷耦合组件319.Electronic shutter 电子快门320.Dynamic range 动态范围321.Temporal resolution 动态分辨率322.Majority carrier 多数载流子323.Amorphous silicon photoconversion layer 非晶硅存储型324.Floating diffusion amplifier 浮置扩散放大器325.Floating gate amplifier 浮置栅极放大器326.Radiant quantity 辐射剂量327.Blooming 高光溢出328.High frame rate readout mode 高速读出模式329.Interlace scan 隔行扫描330.Fixed pattern noise 固定图形噪声331.Photodiode 光电二极管332.Iconoscope 光电摄像管333.Photolelctric effect 光电效应334.Spectral response 光谱响应335.Interline transfer CCD 行间转移型CCD336.Depletion layer 耗尽层plementary metal oxide semi-conductor 互补金属氧化物半导体338.Fundamental absorption edge 基本吸收带339.Valence band 价带340.Transistor 晶体管341.Visible light 可见光342.Spatial filter 空间滤波器343.Block access 块存取344.Pupil compensation 快门校正345.Diffusion current 扩散电流346.Discrete cosine transform 离散余弦变换347.Luminance signal 高度信号348.Quantum efficiency 量子效率349.Smear 漏光350.Edge enhancement 轮廓校正351.Nyquist frequency 奈奎斯特频率352.Energy band 能带353.Bias 偏压354.Drift current 漂移电流355.Clamp 钳位356.Global exposure 全面曝光357.Progressive scan 全像素读出方式358.Full frame CCD 全帧CCD359.Defect correction 缺陷补偿360.Thermal noise 热噪声361.Weak inversion 弱反转362.Shot noise 散粒噪声363.Chrominance difference signal 色差信号364.Colotremperature 色温365.Minority carrier 少数载流子366.Image stabilizer 手振校正367.Horizontal CCD 水平CCD368.Random noise 随机噪声369.Tunneling effect 隧道效应370.Image sensor 图像传感器371.Aliasing 伪信号372.Passive 无源373.Passive pixel sensor 无源像素传感器374.Line transfer 线转移375.Correlated double sampling 相关双采样376.Pinned photodiode 掩埋型光电二极管377.Overflow 溢出378.Effective pixel 有效像素379.Active pixel sensor 有源像素传感器380.Threshold voltage 阈值电压381.Source follower 源极跟随器382.Illuminance 照度383.Refraction index 折射率384.Frame integration 帧读出方式385.Frame interline t ransfer CCD 帧行间转移CCD 386.Frame transfer 帧转移387.Frame transfer CCD 帧转移CCD388.Non interlace 逐行扫描389.Conversion efficiency 转换效率390.Automatic gain control 自动增益控制391.Self-induced drift 自激漂移392.Minimum illumination 最低照度393.CMOS image sensor COMS 图像传感器394.MOS diode MOS 二极管395.MOS image sensor MOS 型图像传感器396.ISO sensitivity ISO 感光度。
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用于光电子器件的低成本、高反射率 SOR衬底(英文)
李成;杨沁青;王红杰;王启明
【期刊名称】《半导体学报：英文版》
【年(卷),期】2001(22)3
【摘要】报道了一种包含一薄层单晶硅和隐埋 Si/Si O2 布拉格反射器的 SOR衬底 .这种可用于光电子器件的衬底是由硅基乳胶粘接和智能剥离技术研制而成的 .在垂直光照条件下 ,这种 SOR衬底在1.3μm处的反射率接近10 0 %
【总页数】4页(P261-264)
【关键词】SOR;光电子器件;衬底;反射率
【作者】李成;杨沁青;王红杰;王启明
【作者单位】中国科学院半导体研究所集成光电子国家重点实验室
【正文语种】中文
【中图分类】TN36
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A mitochondria-targeting near-infrared dye with large Stokes shift and high optical stability for cellular imaging applicationsAbstractMitochondrial imaging is of great significance for studying mitochondrial function and for investigating diseases related to dysfunction in these organelles. Fluorescent dyes have been widely used for imaging mitochondria, however, there are challenges associated with achieving high optical stability and sufficient sensitivity for visualization. In this study, we developed a mitochondria-targeting near-infrared dye with a large Stokes shift and high optical stability for cellular imaging applications. The dye demonstrated excellent mitochondria-targeting ability and low cytotoxicity. Additionally, it displayed a large Stokes shift, which reduces spectral overlap and enables high signal-to-background ratios. This dye provides a powerful tool for mitochondrial imaging and has the potential to advance our understanding of mitochondrial biology and disease.IntroductionMitochondria are organelles that exist within eukaryotic cells, which play a crucial role in energy metabolism, programmed cell death and other cellular processes. Therefore, mitochondrial imaging has significant clinical and research applications, such as in diseases such as cancer, cardiovascular disease and neurological disorders.Fluorescent imaging is commonly used for mitochondrial imaging, but it remains challenging to achieve high optical stability and sufficient sensitivity. This is due to low fluorescence quantum yields of dyes, spectral overlap, and issues with photobleaching, phototoxicity and poor targeting efficiency.In order to overcome these challenges, we have developed a mitochondria-targeting near-infrared dye with a large Stokes shift and high optical stability, which has promising indications for use in cellular imaging applications.Materials and MethodsThe design of the dye was based on a coumarin-based chromophore coupled to a triphenylphosphonium ion (TPP) moiety, which is known for strong mitochondrial targeting. The TPP-coumarin (TPPC) conjugate was synthesized and characterized using standard synthetic methods.Cytotoxicity was measured by incubating the dye with human embryonic kidney cells (HEK293) for 24 hours and assessing cell viability. The mitochondrial-targeting ability of the dye was evaluated using confocal microscopy with MitoTracker as a reference.The optical stability of the dye was assessed through measurements of fluorescence intensity, and photobleaching and photostability tests were also performed.ResultsThe TPPC dye showed excellent mitochondria-targeting ability and low cytotoxicity. Confocal microscopy showed that the dye co-localized with MitoTracker in live cells, indicating that the dye can effectively target and accumulate in the mitochondria.The dye demonstrated a large Stokes shift of 104 nm, which significantly reduces spectral overlap and hence improves signal-to- background ratios, making it an ideal candidate for fluorescence imaging.The dye also showed high optical stability, with fluorescence intensity remaining stable over an extended period of time. Photobleaching and photostability tests demonstrated that the dye is highly resistant to photobleaching, and is maintained at high fluorescence intensity in prolonged exposure to intense light.DiscussionIn this study, we have demonstrated the successful development of a mitochondria-targeting near-infrared dye with a large Stokes shift and high optical stability. The dye showed excellent mitochondrial- targeting ability, low cytotoxicity, high photostability, and a large Stokes shift, indicating great potential for use in cellular imaging applications.With continued research and development, this dye could potentially be used to deepen our understanding of mitochondrial biology and related diseases. Future studies should continue to optimize the design of this dye, and explore its potential as a theranostic tool in targeted drug delivery and disease therapy.ConclusionIn summary, the mitochondria-targeting near-infrared dye with a large Stokes shift and high optical stability developed in this study represents a significant step towards the improvement of cellular imaging applications. The dye showed excellent mitochondrial-targeting ability, low cytotoxicity, and high photostability, and a large Stokes shift. It has the potential to advance our understanding of mitochondrial biology and disease. With further optimization, this research may lead to the development of a potent theranostic tool for targeted drug delivery and disease therapy.。
Advanced Optical MaterialsIntroductionAdvanced optical materials are a class of materials that possess unique optical properties and are engineered to enhance light-matter interactions. These materials have revolutionized various fields such as photonics, optoelectronics, and nanotechnology. In this article, we will explore the different types of advanced optical materials, their applications, and the future prospects of this exciting field.Types of Advanced Optical MaterialsPhotonic CrystalsPhotonic crystals are periodic structures that can manipulate the propagation of light. They consist of a periodic arrangement ofdielectric or metallic components with alternating refractive indices. These structures can control the flow of light by creating energy bandgaps, which prohibit certain wavelengths from propagating through the material. Photonic crystals find applications in optical communication, sensing, and solar cells.MetamaterialsMetamaterials are artificially engineered materials that exhibit properties not found in nature. They are composed of subwavelength-sized building blocks arranged in a periodic or random manner. Metamaterials can manipulate electromagnetic waves by achieving negative refractive index, perfect absorption, and cloaking effects. These unique properties have led to applications in invisibility cloaks, super lenses, and efficient light harvesting.Plasmonic MaterialsPlasmonic materials exploit the interaction between light and free electrons at metal-dielectric interfaces to confine light at nanoscale dimensions. This confinement results in enhanced electromagnetic fields known as surface plasmon resonances. Plasmonic materials have diverse applications such as biosensing, photothermal therapy, and enhanced solar cells.Quantum DotsQuantum dots are nanoscale semiconductor crystals with unique optical properties due to quantum confinement effects. Their size-tunable bandgap enables them to emit different colors of light depending ontheir size. Quantum dots find applications in display technologies (e.g., QLED TVs), biological imaging, and photovoltaics.Organic Optoelectronic MaterialsOrganic optoelectronic materials are based on organic compounds that exhibit electrical conductivity and optical properties. These materials are lightweight, flexible, and can be processed at low cost. They find applications in organic light-emitting diodes (OLEDs), organic photovoltaics (OPVs), and organic field-effect transistors (OFETs).Applications of Advanced Optical MaterialsInformation TechnologyAdvanced optical materials play a crucial role in information technology. Photonic crystals enable the miniaturization of optical devices, leading to faster and more efficient data transmission. Metamaterials offer possibilities for creating ultra-compact photonic integrated circuits. Plasmonic materials enable the development of high-density data storage devices.Energy HarvestingAdvanced optical materials have revolutionized energy harvesting technologies. Quantum dots and organic optoelectronic materials are used in next-generation solar cells to enhance light absorption and efficiency. Plasmonic nanoparticles can concentrate light in solar cells, increasing their power output. These advancements contribute to the development of sustainable energy sources.Sensing and ImagingThe unique optical properties of advanced optical materials make them ideal for sensing and imaging applications. Quantum dots are used as fluorescent probes in biological imaging due to their bright emissionand excellent photostability. Metamaterial-based sensors offer high sensitivity for detecting minute changes in refractive index ormolecular interactions.Biomedical ApplicationsAdvanced optical materials have significant implications in biomedical research and healthcare. Plasmonic nanomaterials enable targeted drug delivery, photothermal therapy, and bioimaging with high spatial resolution. Organic optoelectronic materials find applications in wearable biosensors, smart bandages, and flexible medical devices.Future ProspectsThe field of advanced optical materials is rapidly evolving with continuous advancements being made in material synthesis, characterization techniques, and device fabrication processes. Thefuture prospects of this field are promising, with potential breakthroughs in areas such as:1.Quantum Optics: Integration of advanced optical materials withquantum technologies could lead to the development of quantumcomputers, secure communication networks, and ultra-precisesensors.2.Flexible and Wearable Electronics: Organic optoelectronicmaterials offer the potential for flexible and wearable electronic devices, such as flexible displays, electronic textiles, andimplantable medical devices.3.Optical Computing: Photonic crystals and metamaterials may pavethe way for all-optical computing, where photons replace electrons for faster and more energy-efficient data processing.4.Enhanced Optoelectronic Devices: Continued research on advancedoptical materials will lead to improved performance and efficiency of optoelectronic devices such as solar cells, LEDs, lasers, andphotodetectors.In conclusion, advanced optical materials have opened up newpossibilities in various fields by enabling unprecedented control over light-matter interactions. The ongoing research and development in this field promise exciting advancements in information technology, energy harvesting, sensing and imaging, as well as biomedical applications. The future looks bright for advanced optical materials as they continue to revolutionize technology and shape our world.。
光谱分辨率增强方法品质因子研究
高晓峰;相里斌
【期刊名称】《光子学报》
【年(卷),期】2007(36)6
【摘要】本文提出了一种新的评估光谱复原结果好坏的品质因子(quality factor).该品质因子综合考虑到了前向线性预测和后向线性预测.研究了在不同噪音情况下,当采用伯格法(Burg Method)来求解自回归模型系数时,品质因子随模型阶次的变化以及对复原光谱的影响,并且与芬兰学者Kauppinen提出的品质因子在同等条件下作了详尽的比较.研究结果表明,本文提出的品质因子更具有优越性.
【总页数】5页(P1133-1137)
【关键词】品质因子;线性预测;傅里叶自退卷积;自回归模型
【作者】高晓峰;相里斌
【作者单位】中国科学院西安光学精密机械研究所
【正文语种】中文
【中图分类】TH744
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(19)中华人民共和国国家知识产权局(12)发明专利申请(10)申请公布号 (43)申请公布日 (21)申请号 201910967766.X(22)申请日 2019.10.12(71)申请人 天津大学地址 300072 天津市南开区卫津路92号(72)发明人 华平壤 尹承静 (74)专利代理机构 天津市北洋有限责任专利代理事务所 12201代理人 李素兰(51)Int.Cl.G02B 6/12(2006.01)G02B 6/122(2006.01)G02B 6/13(2006.01)G02B 6/136(2006.01)(54)发明名称一种低损耗铌酸锂薄膜光波导的制备方法(57)摘要本发明公开了一种低损耗铌酸锂薄膜光波导的制备方法，首先采用LNOI作为初始材料；然后在LN薄膜层的表面镀一层100nm厚的SiO 2膜，并对其进行光刻，制作出条状结构的2～3μm宽的SiO 2掩模；接着把光刻后的样品在520～550℃下LRVTE处理10～20个小时，得到LRVTE区域，将所述LRVTE区域的单晶LN薄膜制作成光波导；最后去除SiO 2掩模，并对样品的端面进行抛光处理。
本发明采用LRVTE技术制作的LN薄膜光波导的芯层晶格结构未受损伤，各项光学指标完好地保留了铌酸锂体材料的固有的典型数值，可以实现较低的传输损耗低。
权利要求书1页 说明书3页 附图2页CN 110764185 A 2020.02.07C N 110764185A1.一种低损耗铌酸锂薄膜光波导的制备方法，其特征在于，该方法具体包括以下步骤：首先采用LNOI作为初始材料，然后在LN薄膜层的表面镀一层100nm厚的SiO 2膜，对SiO 2膜进行光刻，制作出条状结构的2～3μm宽的SiO 2掩模，接着把光刻后的条状结构的SiO 2掩模样品在520～550℃下LRVTE处理10～20个小时，得到LRVTE条状区域，将所述LRVTE区域的单晶LN薄膜制作成LN薄膜光波导；最后去除SiO 2掩模，并对样品的端面进行抛光处理。
a r X i v :q u a n t -p h /0212113v 2 11 A p r 2003Stable nondegenerate optical parametric oscillation at degeneratefrequencies in Na:KTPSheng Feng and Olivier Pfister ∗Department of Physics,University of Virginia,382McCormick Road,Charlottesville,VA 22904-4714,USAFebruary 1,2008AbstractWe report the realization of a light source specifi-cally designed for the generation of bright continuous-variable entangled beams and for Heisenberg-limited inteferometry.The source is a nondegenerate,single-mode,continuous-wave optical parametric oscillator in Na:KTP,operated at frequency degeneracy and just above threshold,which is also of interest for the study of critical fluctuations at the transition point.The residual frequency-difference jitter is ±150kHz for a 3MHz cold cavity half-width at half maximum.We observe 4dB of photon-number-difference squeez-ing at 200kHz.The Na:KTP crystal is noncritically phase-matched for a 532nm pump and polarization crosstalk is therefore practically nonexistent.1IntroductionOptical parametric oscillators (OPO’s)are well known sources of nonclassical light.Type-I and type-II OPO’s have been used to generate single-mode [1]and two-mode [2,3]squeezed states and to imple-ment the Einstein-Podolsky-Rosen (EPR)paradox [4]experimentally [2],as proposed in [5,6].The lat-ter has become increasingly important as continuous variables (CV)have been proposed and used to im-plement quantum information protocols [7,8]such as quantum teleportation [9]and quantum dense coding [10].This paper is focused on CV and OPO’s,but one should not forget,of course,that single-photon coincidence detection coupled with spontaneous para-metric downconversion [11]has played a major role in the violation of Bell’s inequalities [12](practically unfeasible with CV),and the realization,for exam-ple,of teleportation [13],multipartite entanglement [14],and very recently quantum computer gates [15].to-degenerate signal and idler frequencies,which isdifficult to achieve because the well-known clustering effect in a doubly resonant type-II OPO puts strin-gent stabilization requirements on the crystal tem-perature,the cavity length,and the pump frequency. One has thus to address two experimental challenges,using a doubly resonant OPO:to achieve stable os-cillation on the frequency degenerate mode and do so close to the threshold,where the output power is theleast stable.We have solved these two issues and present,in this paper,the experimental realization of a stabletype-II OPO,emitting at frequency degeneracy whilepumped only a few percent above threshold.Note that stable twin beams have been achieved before,inparticular in the record-breaking number-differencesqueezing experiments by the group of Fabre and Gi-acobino[3]and in the more recent work of severalother groups[21],but our present work is,to the best of our knowledge,thefirst time that stable twinbeams are obtained at precise frequency degeneracyand just above threshold.Besides bright EPR beam generation,such a source is also extremely interesting for the study of criticalfluctuations at the transition point,including possi-ble generation of macroscopic entanglement[22],and, last but not least,for Heisenberg-limited interferom-etry(HLI).Recall that,if N particles are sent intoan interferometer and subsequently detected or mea-sured,the usual phase sensitivity limit is the inputbeam splitter’s shot noise limit N−1/2[24],whereas the ultimate limit is the Heisenberg limit N−1[25,26].This is a general statement for any bosonfield.Examples of beam splitters are a half-reflecting mir-ror in photon optics and aπ/2resonant laser pulsein atom optics.Reaching the Heisenberg limit re-quires suppressing vacuumfluctuations at the input beam splitter of the interferometer[25],which wasexperimentally demonstrated using vacuum squeez-ing[27].Holland and Burnett[23]also showed thatone can reach the Heisenberg limit by using a sourceof indistinguishable twin modes,i.e.an input density matrix of the formρ= n,mρnm|n n m m|.This was demonstrated using two single-mode amplitude-squeezed beams in Ref.[20],and also a pair of trapped ions[28].Progress has also been made towards real-izing HLI with Bose-Einstein-condensate Fock states [29].It is interesting to note,however,that thecommon-mode statistics(ρnm)n,m do not play anyrole in the phase sensitivity[30],hence generating twin Fock states e.g.|n n is not necessary.There-fore,an OPO emitting intense frequency-degenerate twin beams is an ideal candidate system for HLI,as it would bring,besides the required N−squeezing,the added benefit of a a narrow linewidth CW source, suitable to perform ultra-precise measurements such as gravitational-wave detection.Note also that,since HLI requires large photon numbers,it presents one fewer challenge than bright EPR state generation. In the next section,we describe our experimental setup.We subsequently detail our experimental char-acterization of the source.2Experimental setup2.1OPO crystal and cavityThe Na:KTP crystal noncritically phase-matches type-II degenerate parametric downconversion from 532to1064nm wavelengths along the X axis at room temperature.Such a configuration practically annihilates polarization crosstalk while allowing the convenient use of highly stable Nd:YAG lasers.We use a3×3×10mm3prototype Na:KTP crystal, fabricated by Crystal Associates.The crystal is cut along its X axis,and AR-coated at1064nm and532 nm.It is placed inside an oven made of Oxygen-free,high-conductivity Copper,whose temperature is controlled to less than a millidegree by way of a servo loop.We used two kinds of loopfilters with equal suc-cess,one home-made and one commercial from Wave-length Electronics.Tight temperature control of the nonlinear crystal is paramount in a type-II OPO be-cause of the different temperature dependences of the indices of refraction for the two cross-polarized reso-nant signal and idler waves.The OPO has a standing-wave cavity formed by two plano-concave mirrors that have a radius of cur-vature of5cm and are separated by approximately 10.2cm,thereby realizing a concentric resonator. One of the mirrors is mounted on a piezoelectric transducer(PZT).The cavity waist size is in between the Boyd-Ashkin confocal-focusing value w o(BA)=ilyfind a cavity mode that coincides with the crys-tal’s X axis so as to completely eliminate walkoff. The OPO alignment procedure consists of aligning the resonator without the crystalfirst,and then in-serting the crystal and orienting it between crossed polarizers in order to align the X axis with the cav-ity axis.The cavity is then used as a resonant fre-quency doubler in order to optimize the crystal tem-perature for maximum SHG efficiency,which corre-sponds to the lowest OPO threshold.The SHG pump laser at1064nm(Lightwave Electronics126-700-1064)is,once frequency-doubled,heterodyned with the OPO pump laser(Lightwave Electronics142)and the resulting beat note at their frequency differenceis tuned to zero.The reflectivities of the OPO mir-rors are R(1064nm)=0.999and R(532nm)=0.6 for the input coupler,and R(1064nm)=0.990and R(532nm)=0.1for the output coupler.The OPO is therefore essentially doubly resonant for the signal and the idler.2.2OPO stabilizationIn order to ensure single-mode oscillation within the dense cluster structure(seebelow),we use stan-dard laser stabilization techniques[32],which per-mit cavity-length control at the femtometer level[33]. The OPO cavity is electronically stabilized by two servo loops,one for temperature and one for cav-ity length(Fig.1).The cavity-length error signal is Figure1:Experimental setup.DM:Dichroic mirror (reflects532nm;transmits1064nm).picked offthe small leak through the HR input cou-pler.A sinusoidal voltage at25kHz excites thefirst mechanical resonance of the PZT-mirror system and serves to modulate the OPO frequency.The weak leak signal is demodulated by a lock-in amplifier,pro-cessed by a loopfilter,andfinally applied to the OPO PZT.The good signal-to-noise ratio of this method allows us to operate with the OPO a few percent above threshold,which is of interest for quantum op-tics with bright beams as it will allow us to easily perform homodyne squeezing measurements with a stronger local oscillator,something believed difficult [17]because of the current power-withstanding limi-tations of high-efficiency photodiodes.2.3DetectionThe OPO signal and idler beams are collimated by an AR-coated lens and then traverse a variable beam splitter comprised of a half-wave plate followed by a low loss polarizing beam splitter(T p,R s>0.99).We Figure2:(a):Intensity difference spectrum of twin beams through a balanced beam splitter(half-wave plate@π/8rad).The4MHz signal-idler beat note is clearly visible,along with its second harmonic (preamplifier distortion).(b):Intensity difference spectrum of twin beams(half-wave plate@0rad). The residual4MHz beat note is52dB below its maximum level offig.2(a).(No intensity squeezing is visible here because the OPO beams are attenu-ated before detection.)Resolution bandwidth:100kHz.Single sweeps.determine the reference angle of the wave plate axes α=0by minimizing the beat note on the detectors,which clearly separates the twin beams.For otherangles relative to this one,the beams are thus mixedin the equivalent way to a beam splitter with reflec-tivity R=cos2(2α).Whenα=π=∆s,i dp s,iλs,i .(1)dLFrom this equation,onefinds the well-known mini-mum length variationδL=±λ/2for which a modehop(δp=∓1,δν=0)occurs,in the case of asingly-resonant OPO or laser.In a doubly-resonantOPO,the additional constraint that both frequen-cies sum up to the pump frequencyνp=νs+νimodifies the length tuning of the OPO cavity in adramatic way,as the OPO will not lase for all com-binations of the signal and idler modes.The result isa tightly packed cluster structure.For a stable andnarrow pump frequency,which is the case here,onehas d(νs+νi)/dL=0.The length displacements cor-responding to mode hops are then given by,tofirstorder in the birefringenceδn=n s−n i,δL≃ (δp s+δp i)+1¯n+L/ℓ(δp s−δp i) λpwhereλp is the pump wavelength,¯n=(n s+n i)/2,Figure4:OPO beat note spectrum,5MHz span. The narrow peaks are single spectrum analyzer sweeps(14ms),and the broad features are the corre-sponding“max hold”traces for one minute or more.(a):Free-running OPO4times above threshold.The HWHM of the narrow peak is50kHz and the drift range is2MHz.Free-running oscillation stays single-mode without servo because the OPO mode HWHM is of the order of10MHz(the cluster modes overlap. See text).(b):Frequency-locked OPO four times above threshold.The narrow HWHM is60kHz and the drift range is310kHz,only limited by the signal-to-noise ration of the servo error signal.Note that the fast beat-note linewidth is limited by the30kHz resolution bandwidth of the analyzer.andδp s,i are integers.Mode clusters are labeled by (δp s+δp i)and separated by half a pump wavelength. Inside a given cluster,the modes are labeled by(δp s−δp i)and separated by(δp s=−δp i=±1)δL min≃δn2≪λp,(3)the signal-idler frequency difference or beat noteνb=νs−νi differing,between two consecutive modes,by the sum of the FSR’s.In the case of our experiment,¯n=1.8,δn=0.09,L=9.2cm,andλp=532nm, give clusters every266nm with mode hopsδL min≃λp∂L T,V,νp=(−5.11,−0.02)MHz/nm;(5) ∂ν±∂V L,T,νp=(1.34,0.59)MHz/V;(7) ∂ν±both sharing in particular sharp resonancesat 70and 100Hz.This produces noise on ν±,and Eq.(5)shows that the cavity length servo is ill-equipped to do much correction on ν−because of the low tuning coefficient.As already mentioned,the temperature servo is too slow to be useful here,hence further narrowing of the beat note spectrum will require an electro-optic servo on the crystal so as to make use of the favorable tuning coefficient of Eq.(7).Note,however,that the current level of perfor-mance is already outstanding and satisfactory for EPR and HLI experiments,the beat note being tun-able to exactly zero hertz (within the residual jitter range)by a simple temperature adjustment.3.3Intensity controlIn order to determine how close to the threshold the OPO can stably be operated,which is crucial in order to determine whether EPR correlations can be ob-served,we have investigated the conversion efficiency given by [31]ρ=P outP p=KN −1),(9)where N =P p /P th is the number of times above threshold (and should be as close to 1as possible)and K is a constant whose value is 2for a standing wave cavity with a single-pass pump and up to 4if the pump is reflected,the value of 4corresponding to a ring resonator or to a double-pass pump with the right phase relationship with the signal and idler fields δφ=φp −φs −φi =−π/2[36].The value of K therefore depends on the differential phase shift im-parted to δφby reflection on the OPO output mirror and on air dispersion.We measured the OPO out-put power for different values of the pump power for the frequency-degenerate mode in stably locked con-ditions.Figure 5displays a plot of ρversus P p ,as well as a least-squares fit using Eq.(9).Since we do not know the mirror’s phase shift,we leave K as a free parameter in the fit.The lowest point on the plot cor-responds to N =1.04,ρ=5%,and P out =700µW per beam.We have in fact observed stable oscillation for N as low as 1.01,i.e.output powers of a few hun-dred microwatts per beam.This should indeed be in the regime where EPR correlations are expected [5].The OPO output noise on each individual beam is mainly that of the pump laser,i.e.fairly low (but with relaxation oscillations)and is shot-noise limited above 1.5MHz.As already seen on fig.3,intensity-difference measurements are shot-noise limited above 200kHz.This speaks to the low level of classical in-tensity noise.Figure 4(a)also gives an idea of longer-0.70.60.50.40.30.20.10.0O P O c o n v e r s i o n e f f i c i e n c y6055504540353025Pump power (mW)Figure 5:Measurement and fit of the conversion ef-ficiency of the OPO locked on the degenerate mode.ρ=KN −1),where N =P p /P th .Fit parameters are P th =25.6(2)mW,K =3.26(6),χ2=1.510−3.term intensity fluctuations of the unlocked OPO in a single-detector measurement.The theoretical threshold is 12mW [31].We mea-sured about 15mW for the strongest cluster mode and 25.6(2)mW for the degenerate mode,which is not the strongest (center)cluster mode.This is due to a slight misalignment of the phase-matching angle of the crystal.Correcting it is quite doable but is always a delicate operation as it couples to the cavity alignment.We observe that the power level of the degenerate mode remains remarkably constant over time,even with the experiment (including the pump laser)turned offeach night,testifying to the stability of the optical alignments.It is possible to achieve even lower powers with the same threshold,but the capture range of the servo decreases as the gain linewidth and this degrades the locking performance.We are currently implementing lower-noise detection techniques aiming at increasing the signal-to-noise ratio by one order of magnitude and at expanding the capture range of the servo.One should also note that,since the error signal is mixed with a considerable amount of vacuum fluctu-ations (99.99%),we only use a classical signal to lock.As a consequence,our servo cannot correct quantum fluctuations,be they phase difference noise or critical threshold fluctuations,which will allow us to observe them without interference from the locking electron-ics.4ConclusionWe have experimentally demonstrated the stable op-eration of a frequency degenerate type-II OPO above threshold,with negligible polarization crosstalk,us-ing a noncritically phase-matched Sodium-doped KTP nonlinear crystal.The degenerate mode is ob-tained reproducibly without the need to realign the OPO cavity after the initial alignment,and its inten-sity is controlled as low as just a few percent above threshold.The twin beams exhibit4dB of 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