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奇偶q-变形相干态的高阶压缩效应 被引量:21
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作者 汪仲清 《物理学报》 SCIE EI CAS CSCD 北大核心 2001年第4期90-92,共3页
研究了奇偶 q 变形相干态中光场的高阶压缩效应 .数值计算结果发现 ,奇偶 q 变形相干态中光场的高阶压缩效应与参数值 q有关 ,当参数q取偏离 1较大的值时 ,q 变形奇偶相干态均可具有奇次方阶压缩效应却无偶次方阶压缩效应 。
关键词 光场 q-变形相干态 高阶压缩效应 振幅
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激发双模压缩真空态的等阶Y压缩效应 被引量:11
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作者 张敏 《量子电子学报》 CAS CSCD 北大核心 2003年第5期561-565,共5页
本文研究了激发双模压缩真空态a+mb+m|ξ〉的等阶Y压缩效应。数值计算的结果表明:对于态a+mb+m|ξ〉,光场存在着等阶K(=2,3,4,5,…)次方Y压缩效应,而且随着场模上光子增加数m的增大,等阶K次方Y压缩效应增强。
关键词 光场 激发双模压缩真空态 等阶K次方Y压缩效应 等阶Y压缩度 量子光学
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非旋波近似下双光子Jaynes-Cummings模型中光子反聚束效应的研究 被引量:5
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作者 谢瑞华 刘敦桓 《光学学报》 EI CAS CSCD 北大核心 1996年第7期933-937,共5页
利用弱场-弱耦合-短时近似,研究了旋波近似与非旋波近似下双光子Jaynes-Cummings模型(JCM)中光子的反聚束效应,分析了虚光子过程对此效应的影响。
关键词 光子 反聚束效应 双光子 J-C模型 量子光学
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混合态二能级原子双光子过程的粒子数反转特性 被引量:5
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作者 聂义友 雷敏生 谢芳森 《光子学报》 EI CAS CSCD 1999年第7期591-595,共5页
本文采用时间演化算符方法和数值计算研究了相干光场与混合态二能级原子双光子过程的粒子数反转特性,结果表明:量子崩塌与复苏性质和原子初始的混合程度无关,但振荡最大幅值受原子初始混合程度的支配,随着原子初始混合程度的增大,... 本文采用时间演化算符方法和数值计算研究了相干光场与混合态二能级原子双光子过程的粒子数反转特性,结果表明:量子崩塌与复苏性质和原子初始的混合程度无关,但振荡最大幅值受原子初始混合程度的支配,随着原子初始混合程度的增大,原子反转几率减小;在强场作用下,这种量子崩塌与复苏性质,将随着n值的不断增大而重复地出现复苏收缩现象。 展开更多
关键词 统计混合态 双光子 粒子数反转 二能级原子
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增加光子双模压缩真空态的N次方H压缩效应 被引量:5
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作者 江俊勤 《量子电子学报》 CAS CSCD 北大核心 2004年第6期850-854,共5页
通过数值计算,研究了增加光子双模压缩真空态的N次方H压缩效应。结果表明:对于态,光场存在着N次方H压缩效应,而且对于高次方H压缩,在压缩参数较大时,随着场模上光子增加数的增大,N次方H压缩效应增强.
关键词 量子光学 光场 增加光子双模压缩真空态 N次方H压缩效应 H压缩度
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Long Range, Long Lived and Gauge Invariant Massive Photons via Stückelberg Scalar Coupling 被引量:1
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作者 Golden Gadzirayi Nyambuya 《Journal of Modern Physics》 2016年第1期7-24,共18页
It is largely believed (or strongly assumed) that photons are massless particles and the most compelling evidence there—it is said—is found in the manifestations of photons being long ranged and long lived particles... It is largely believed (or strongly assumed) that photons are massless particles and the most compelling evidence there—it is said—is found in the manifestations of photons being long ranged and long lived particles. As we have done before, albeit, with a much better and clear insight in the present than before;we argue herein that massive photons can still enjoy the special and rare privilege of travelling at the speed of light c while being long ranged, long lived and most of all, obeying the much desired gauge symmetry. This we achieve by breaking the traditional Lorenz gauge and in its place, we introduce a new Special Gauge Condition (SGC) that does the work of assuring the photon its longevity, long range-ness and that it [photon] propagates at the speed c. However, the most melancholic outcome of our investigation is that if the present scheme is what subtle Nature has chosen to endow the photon a non-zero mass so that it [photon] still obeys gauge invariance, is long ranged, long lived and travels at the sacred speed c;then, this non-zero photon mass may be very difficult, if not impossible to measure. We use the equations developed to investigate Lorentz violation in ?-ray bursts. 展开更多
关键词 Lorentz Violation Lorenz Gauge: Violation Stueckelberg: field Mechanism-Proca: Massive photon Long Range photon Long Lived photon
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The Size of a Photon
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作者 Richard A. Hutchin 《Optics and Photonics Journal》 2021年第5期121-131,共11页
This paper begins by exploring a useful and neglected detail of a photon—its physical size perpendicular to the direction of propagation in the same way as an atom or neutron has a physical size. Such a photon size w... This paper begins by exploring a useful and neglected detail of a photon—its physical size perpendicular to the direction of propagation in the same way as an atom or neutron has a physical size. Such a photon size would be quite separate from the cross-section of a photonic interaction, which depends on the material interacting. Such a perpendicular dimension of a photon will be invariant under Lorentz transform parallel to the light propagation direction and will thus be the same for all frequencies of light. This study also leads to new details about how a photon interacts, offering an explanation for the familiar physics where light slightly above and below the mean frequency of an excited state can still excite the same state without violation of conservation of energy—a mystery explored thoroughly in a previous paper without finding the solution offered here. As usual, a better elucidation of the details of light interaction also leads to new insights—especially about the vacuum field. The <strong>Appendix </strong>summarizes some previous research relevant to this 展开更多
关键词 photon Size photon Energy photon Excitation Vacuum field Red Shift
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Electromagnetism According to Maxwell’s Initial Interpretation
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作者 André Michaud 《Journal of Modern Physics》 2020年第1期16-80,共65页
It is well established that classical electrodynamics, quantum electrodynamics (QED) as well as Quantum Field Theory (QFT) are grounded on Maxwell’s wave theory and on his equations, but it is much less well understo... It is well established that classical electrodynamics, quantum electrodynamics (QED) as well as Quantum Field Theory (QFT) are grounded on Maxwell’s wave theory and on his equations, but it is much less well understood that they are not grounded on his initial interpretation of the relation between the E and B fields, but are rather grounded on Ludvig Lorenz’s interpretation of this relation, with which Maxwell disagreed. Maxwell considered that both fields had to mutually induce each other cyclically for the velocity of light to be maintained while Lorenz considered that both fields had to synchronously peak at maximum at the same time for this velocity to be maintained, both interpretations being equally consistent with the equations. Two recent breakthroughs however now allow confirming that Maxwell’s interpretation was correct because, contrary to the Lorenz interpretation, it allows to seamlessly reconcile Maxwell’s electromagnetic wave theory, so successfully applied at our macroscopic level, with the electromagnetic characteristics that apply at the subatomic level to localized electromagnetic photons and to all localized charged and massive elementary electromagnetic particles of which all atoms are made, and finally allows establishing a clear mechanics of electromagnetic photon emission and absorption by electrons during their interaction at the atomic level. 展开更多
关键词 MAGNETIC Mass MAGNETIC field Electric field Electron photon Emission photon ABSORPTION
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MRI引导放射治疗中电子回转效应的蒙特卡罗研究 被引量:4
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作者 游士虎 胡南 +4 位作者 吴章文 刘岩海 吴骏翔 侯氢 勾成俊 《原子核物理评论》 CAS CSCD 北大核心 2015年第3期363-367,共5页
为了研究磁共振引导放射治疗对剂量分布的影响,采用蒙特卡罗方法研究了横向均匀磁场对6 MV光子束在4种不同人体组织材料与空气界面处因电子回转效应导致剂量分布的改变。模拟显示,对于电离能相近的几种材料,磁场对剂量分布扰动的差别较... 为了研究磁共振引导放射治疗对剂量分布的影响,采用蒙特卡罗方法研究了横向均匀磁场对6 MV光子束在4种不同人体组织材料与空气界面处因电子回转效应导致剂量分布的改变。模拟显示,对于电离能相近的几种材料,磁场对剂量分布扰动的差别较小,而且电离能较大的材料,这种扰动明显变小。结果表明,磁场的引入会影响光子束原有的剂量分布,且这种影响与材料的电离能有关。这意味着虽然磁共振引导放射治疗可以增强靶向精度,提高治疗效果,但磁场会导致光子束剂量分布的改变,且不同的组织这种改变也不相同,这将为相应的剂量算法研究带来了新的挑战。 展开更多
关键词 放射治疗 光子束 磁场 蒙特卡罗
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Photon retention in coherently excited nitrogen ions 被引量:4
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作者 Jinping Yao Luojia Wang +12 位作者 Jinming Chen Yuexin Wan Zhihao Zhang Fangbo Zhang Lingling Qiao Shupeng Yu Botao Fu Zengxiu Zhao Chengyin Wu Vladislav VYakovlev Luqi Yuan Xianfeng Chen Ya Cheng 《Science Bulletin》 SCIE EI CSCD 2021年第15期1511-1517,M0003,共8页
Quantum coherence in quantum optics is an essential part of optical information processing and light manipulation.Alkali metal vapors,despite the numerous shortcomings,are traditionally used in quantum optics as a wor... Quantum coherence in quantum optics is an essential part of optical information processing and light manipulation.Alkali metal vapors,despite the numerous shortcomings,are traditionally used in quantum optics as a working medium due to convenient near-infrared excitation,strong dipole transitions and long-lived coherence.Here,we proposed and experimentally demonstrated photon retention and subsequent re-emittance with the quantum coherence in a system of coherently excited molecular nitrogen ions(N_(2)^(+))which are produced using a strong 800 nm femtosecond laser pulse.Such photon retention,facilitated by quantum coherence,keeps releasing directly-unmeasurable coherent photons for tens of picoseconds,but is able to be read out by a time-delayed femtosecond pulse centered at 1580 nm via two-photon resonant absorption,resulting in a strong radiation at 329.3 nm.We reveal a pivotal role of the excited-state population to transmit such extremely weak re-emitted photons in this system.This new finding unveils the nature of the coherent quantum control in N_(2)^(+)for the potential platform for optical information storage in the remote atmosphere,and facilitates further exploration of fundamental interactions in the quantum optical platform with strong-field ionized molecules. 展开更多
关键词 Quantum coherence photon retention Coherent quantum control Strong-field ionized molecules
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3D printed multicore fiber-tip discriminative sensor for magnetic field and temperature measurements
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作者 Cong Xiong Caoyuan Wang +6 位作者 Ruowei Yu Wei Ji Yu Qin Yichun Shen Wei Chen Ai-Qun Liu Limin Xiao 《Light(Advanced Manufacturing)》 2024年第1期82-92,共11页
Miniaturized fiber-optic magnetic field sensors have attracted considerable interest owing to their superiorities in anti-electromagnetic interference and compactness.However,the intrinsic thermodynamic properties of ... Miniaturized fiber-optic magnetic field sensors have attracted considerable interest owing to their superiorities in anti-electromagnetic interference and compactness.However,the intrinsic thermodynamic properties of the material make temperature cross-sensitivity a challenging problem in terms of sensing accuracy and reliability.In this study,an ultracompact multicore fiber(MCF)tip sensor was designed to discriminatively measure the magnetic field and temperature,which was subsequently evaluated experimentally.The novel 3D printed sensing component consists of a bowl-shaped microcantilever and a polymer microfluid-infiltrated microcavity on the end-facet of an MCF,acting as two miniaturized Fabry-Perot interferometers.The magnetic sensitivity of the microcantilever was implemented by incorporating an iron micro ball into the microcantilever,and the microfluid-infiltrated microcavity enhanced the capability of highly sensitive temperature sensing.Using this tiny fiber-facet device in the two channels of an MCF allows discriminative measurements of the magnetic field and temperature by determining the sensitivity coefficient matrix of two parameters.The device exhibited a high magnetic field intensity sensitivity,approximately 1805.6 pm/mT with a fast response time of~213 ms and a high temperature sensitivity of 160.3 pm/℃.Moreover,the sensor had a low condition number of 11.28,indicating high reliability in two-parameter measurements.The proposed 3D printed MCF-tip probes,which detect multiple signals through multiple channels within a single fiber,can provide an ultracompact,sensitive,and reliable scheme for discriminative measurements.The bowl-shaped microcantilever also provides a useful platform for incorporating microstructures with functional materials,extending multi-parameter sensing scenarios and promoting the application of MCFs. 展开更多
关键词 Two-photon polymerization Multicore fiber-tip sensor Magnetic field sensing Discriminative sensing
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The Weak Magnetic Photon Emission from Quark-gluon Plasma
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作者 SUN Jing’an YAN Li 《原子核物理评论》 CAS CSCD 北大核心 2024年第1期558-563,共6页
There must be electromagnetic fields created during high-energy heavy-ion collisions.Although the electromagnetic field may become weak with the evolution of the quark-gluon plasma(QGP),compared to the energy scales o... There must be electromagnetic fields created during high-energy heavy-ion collisions.Although the electromagnetic field may become weak with the evolution of the quark-gluon plasma(QGP),compared to the energy scales of the strong interaction,they are potentially important to some electromagnetic probes.In this work,we propose the coupled effect of the weak magnetic field and the longitudinal dynamics of the background medium for the first time.We demonstrate that the induced photon spectrum can be highly azimuthally anisotropic when the quarkgluon plasma is in the presence of a weak external magnetic field.On the other hand,the weak magnetic photon emission from quark-gluon plasma only leads to a small correction to the photon production rate.After hydrodynamic evolution with a tilted fireball configuration,the experimentally measured direct photon elliptic flow is well reproduced.Meanwhile,the used time-averaged magnetic field in the hydrodynamic stage is found no larger than a few percent of the pion mass square. 展开更多
关键词 heavy-ion collision the direct photon weak magnetic field elliptic flow
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The Essence of Microscopic Particles and Quantum Theory
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作者 Xiangyao Wu Benshan Wu +1 位作者 Qiming Wu Hong Li 《Journal of Modern Physics》 CAS 2023年第5期755-776,共22页
In the paper, we have given the quantum equation of the gravitational field intensity E<sub>g </sub>(r, t) and electric field intensity E (r, t) for the material particles, since the gravita... In the paper, we have given the quantum equation of the gravitational field intensity E<sub>g </sub>(r, t) and electric field intensity E (r, t) for the material particles, since the gravitational field intensity E<sub>g </sub>(r, t) and electric field intensity E (r, t)  is in direct proportion to the distribution function ψ (r, t) of particle spatial position (wave function), these quantum equations are natural converted into the Schrodinger equation. In addition, we have proposed the new model about the photon and matter particles. For all particles, they are not point particles, but they have a very small volume. The photon has a vibration electric field in its very small volume. The neutral material particle, such as neutron, it has a vibration gravitational field in its very small volume. For the charge material particles, such as electron and proton, they have both vibration gravitational field and vibration electric field in their very small volume. With the model, we can explain the diffraction and interference of single slit and multiple-slit for the single photon and material particles, the volatility of all particles come from the superposition of their respective vibration field. After the vibration field of particle superposition, it shows up as a particle property. On this basis, We have obtained some new results, and realized the unification of both wave and particle and field and matter. 展开更多
关键词 photon Material Particles Electromagnetic field Gravitational field Schrodinger Equation
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Fluorescence correlation spectroscopy in laser gradient field 被引量:2
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作者 Fanbo Meng Bo Chen +3 位作者 Yao Ding Hui Ma Lei Jin Dieyan Chen 《Chinese Science Bulletin》 SCIE EI CAS 2001年第19期1589-1592,共4页
Fluorescence correlation spectroscopy (FCS) is capable of probing dynamic processes in living biological systems. From photon fluctuation of fluorescing particles which diffuse through a small detection volume, FCS re... Fluorescence correlation spectroscopy (FCS) is capable of probing dynamic processes in living biological systems. From photon fluctuation of fluorescing particles which diffuse through a small detection volume, FCS reveals information on the concentration and the structure of the particles, as well as information on microscopic environment. In this note, we study the radiation forces experienced by Rayleigh particles in a laser field in details, and analyze the effects of gradient field on FCS measurements. 展开更多
关键词 FLUORESCENCE CORRELATION SPECTROSCOPY GRADIENT field BROWNIAN motion TWO-photon fluorescence.
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基于QNX的启动和终止远程进程方法的研究与实现 被引量:2
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作者 段菖蒲 傅鹏 《化工自动化及仪表》 EI CAS 2005年第6期33-36,39,共5页
针对目前EAST极向场电源控制系统操作方式所存在的问题,通过对QNX的Photon m icroGUI(微图形用户接口)的运行机理及QNX网络体系结构的分析,重点对如何利用spawn()和PtTty控件启动和终止远程进程的方法进行了研究,通过对比分析,总结出一... 针对目前EAST极向场电源控制系统操作方式所存在的问题,通过对QNX的Photon m icroGUI(微图形用户接口)的运行机理及QNX网络体系结构的分析,重点对如何利用spawn()和PtTty控件启动和终止远程进程的方法进行了研究,通过对比分析,总结出一种既简便易行,又能可靠地启动和终止远程进程的方法。 展开更多
关键词 EAST 极向场 QNX 远程进程 伪终端 photon 事件空间 事件 区域
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Photon Is Shortened Name for Electromagnetic Field but Not a Particle 被引量:1
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作者 Marat Vladimirovich Guryev 《Journal of Applied Mathematics and Physics》 2018年第9期1883-1885,共3页
We well know that photon concept is self-contradictory because we assume that it is a particle with wave properties. This contradiction insensibly spoils our subconscious thinking. It is shown in the article that phot... We well know that photon concept is self-contradictory because we assume that it is a particle with wave properties. This contradiction insensibly spoils our subconscious thinking. It is shown in the article that photon has no 4-coordinates for work within atomic quantum electrodynamics (QED). This implies that actually photon is not a particle. I draw attention that QED is the most precise theory developed by humankind. It is noticed that terms photon and electromagnetic field in practice are in use as synonyms. These results validate the title of the article and exempt us from contradictions within quantum mechanics. 展开更多
关键词 photon QUANTUM JUMPS Quantization Quant 4-Coordinates of a PARTICLE Electromagnetic field QUANTUM ELECTRODYNAMICS
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光的波粒二象性探索 被引量:2
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作者 刘中亮 李一辰 +1 位作者 刘洪 仝辉 《数学的实践与认识》 CSCD 北大核心 2012年第14期98-106,共9页
光具有波粒二象性,但很难从光的某一特定现象中同时看到这两种性质.如果能用粒子性解释波动性,光的两种性质就能得到完美的统一.分别对龚祖同光子模型、前进电磁场光子模型进行数学建模和MATLAB仿真,并与已有的实验结果比较.发现两个模... 光具有波粒二象性,但很难从光的某一特定现象中同时看到这两种性质.如果能用粒子性解释波动性,光的两种性质就能得到完美的统一.分别对龚祖同光子模型、前进电磁场光子模型进行数学建模和MATLAB仿真,并与已有的实验结果比较.发现两个模型都存在不足,进而提出改进的光子模型,从粒子的角度,对展现光的波动性质的干涉、衍射以及偏振现象进行解释. 展开更多
关键词 波粒二象性 光子 电磁场 干涉 偏振
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Space-time description of transverse photons: near-field aspects 被引量:1
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作者 KELLER O. 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第8期1389-1393,共5页
A mean position state based on the gauge invariant transverse vector potential is used to convert single-photon states in Hilbert space to photon wave packets in direct space. The resulting photon wave-mechanical desc... A mean position state based on the gauge invariant transverse vector potential is used to convert single-photon states in Hilbert space to photon wave packets in direct space. The resulting photon wave-mechanical description leads to scalar products which relate to covariant integration on the light cone. A new correlation matrix displays the spatial localization problem for single photons in an explicit manner in space-time. The correlation matrix essentially is the projection of the time-ordered Feynman photon propagator onto the transverse photon subspace. The present photon wave-mechanical formalism is generalized to two-photon dynamics. In the diamagnetic limit the transverse photon becomes massive in its interaction with matter, and the correlation matrix for massivephoton interaction, which can be used in studies of evanescent-photon mediated couplings, is analyzed. On the basis of the present formalism the existence of a dynamical near-field Aharonov-Bohm effect is predicted. 展开更多
关键词 one-photon wave mechanics near-field optics correlation matrix transverse photon mass
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Fast fluorescence lifetime imaging techniques:A review on challenge and development 被引量:1
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作者 Xiongbo Liu Danying Lin +4 位作者 Wolfgang Becker Jingjing Niu Bin Yu Liwei Liu Junle Qu 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2019年第5期3-29,共27页
Fluorescence lifetime imaging microscopy(FLIM)is increasingly used in biomedicine,material science,chemistry,and other related research fields,because of its advantages of high specificity and sensitivity in monitorin... Fluorescence lifetime imaging microscopy(FLIM)is increasingly used in biomedicine,material science,chemistry,and other related research fields,because of its advantages of high specificity and sensitivity in monitoring cellular microenvironments,studying interaction between proteins,metabolic state,screening drugs and analyzing their efficacy,characterizing novel materials,and diagnosing early cancers.Understandably,there is a large interest in obtaining FLIM data within an acquisition time as short as possible.Consequently,there is currently a technology that advances towards faster and faster FLIM recording.However,the maximum speed of a recording technique is only part of the problerm.The acquisition time of a FLIM image is a complex function of many factors.These include the photon rate that can be obtained from the sample,the amount of information a technique extracts from the decay functions,the fficiency at which it determines fluorescence decay parameters from the recorded photons,the demands for the accuracy of these parameters,the number of pixels,and the lateral and axial resolutions that are obtained in biological materials.Starting from a discussion of the parameters which determine the acquisition time,this review will describe existing and emerging FLIM techniques and data analysis algo-rithms,and analyze their performance and recording speed in biological and biomedical applications. 展开更多
关键词 Fluorescence lifetime imaging microscopy(FLIM) acquisitin time imaging speed dead time photon fficiency time domain frequency domain scanning wide-field imaging time-correlated single photon counting(TCSPC) gated detection gated image intensifer modulated inage intensifier SPAD array detector
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单原子微波激射器中光场N阶压缩效应的研究 被引量:1
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作者 任珉 马爱群 《烟台师范学院学报(自然科学版)》 1993年第2期21-26,共6页
利用Jaynes-Cummings模型研究单原子微波激射器中光场的N阶压缩效应,得到了该场N阶压缩的一般表达式;详细讨论了初始光场是真空场和n光子光场的N阶压缩的行为.
关键词 单原子 微波激射器 光场 N阶压缩
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