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鱼油n-3 PUFA富集、稳态化技术及生物活性研究进展
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作者 刘书源 郭明珠 +2 位作者 马爱进 桑亚新 孙纪录 《中国食品学报》 EI CAS CSCD 北大核心 2024年第2期467-478,共12页
鱼油富含人体所需的多不饱和脂肪酸,在科研与应用领域具有广泛价值。本文重点围绕其n-3 PUFA富集工艺、稳态化技术及生物活性进行综述,阐述不同方法的优、缺点,分析工业化生产的可行性,展望未来鱼油加工领域的发展趋势,旨在为鱼油类资... 鱼油富含人体所需的多不饱和脂肪酸,在科研与应用领域具有广泛价值。本文重点围绕其n-3 PUFA富集工艺、稳态化技术及生物活性进行综述,阐述不同方法的优、缺点,分析工业化生产的可行性,展望未来鱼油加工领域的发展趋势,旨在为鱼油类资源的合理、健康、可持续发展提供理论依据。 展开更多
关键词 鱼油 富集工艺 稳态化 n-3 PUFA
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Mon(n=2-13)和MonC(n=1-12)团簇的几何结构和电子结构
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作者 杨文辉 相悦 +1 位作者 陈轩 段海明 《原子与分子物理学报》 北大核心 2024年第6期52-59,共8页
结合遗传算法和CALYPSO软件,采用密度泛函理论,对Mon(n=2-13)及MonC(n=1-12)团簇基态的几何结构与电子结构展开详细研究.通过计算其基态结构的平均键长、平均结合能、二阶差分能、分裂能和前线轨道能级,对基态结构的稳定性随总原子数变... 结合遗传算法和CALYPSO软件,采用密度泛函理论,对Mon(n=2-13)及MonC(n=1-12)团簇基态的几何结构与电子结构展开详细研究.通过计算其基态结构的平均键长、平均结合能、二阶差分能、分裂能和前线轨道能级,对基态结构的稳定性随总原子数变化的关系展开了研究.计算结果表明,Mon团簇基态结构的稳定性可通过掺杂单个C原子而提高.综合团簇的二阶差分能、分裂能可知,n=6,9时Mon团簇的稳定性较高,n=4,7,10时MonC团簇的稳定性较高. 展开更多
关键词 密度泛函理论 Mon团簇 MonC团簇 基态结构 电子性质
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N量子比特系统的纠缠判据
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作者 谭维翰 赵超樱 郭奇志 《物理学报》 SCIE EI CAS CSCD 北大核心 2023年第1期9-18,共10页
在前文(2019 Int. J.Mod.Phys.B 33 1950197;2020 Int.J.Mod.Phys.B 34 2050022)中,我们提出了一种判断2量子比特系统纠缠的方法,2量子比特系统可分的充分必要条件是相关系数为正且主密度矩阵可分,否则系统纠缠.在本文中,通过数值计算... 在前文(2019 Int. J.Mod.Phys.B 33 1950197;2020 Int.J.Mod.Phys.B 34 2050022)中,我们提出了一种判断2量子比特系统纠缠的方法,2量子比特系统可分的充分必要条件是相关系数为正且主密度矩阵可分,否则系统纠缠.在本文中,通过数值计算与讨论,先将2量子比特系统纠缠判据的方法推广到3量子比特系统中去;接着,继续将3量子比特系统推广到N量子比特系统中去.这是一个复杂而有趣的问题. 展开更多
关键词 玻恩几率密度 n量子比特系统 纠缠态
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A new representation and probabilistic teleportation of an arbitrary and unknown N-particle state 被引量:6
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作者 董莉 修晓明 高亚军 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第12期2835-2839,共5页
A new representation of an arbitrary and unknown N-particle state is presented at first. As an application, a scheme for teleporting an arbitrary and unknown N-particle state is proposed when N pairs of two-particle n... A new representation of an arbitrary and unknown N-particle state is presented at first. As an application, a scheme for teleporting an arbitrary and unknown N-particle state is proposed when N pairs of two-particle non- maximally entangled states are utilized as quantum channels. After Alice (sender) makes Bell-state measurement on her particles, Bob (recipient) introduces an auxiliary particle and carries out appropriate unitary transformation on his particle and the auxiliary particle depending on classical information from Alice. Then, von Neumann measurement that confirms whether the teleportation succeeds or not is performed by Bob on the auxiliary particle. In order to complete the teleportation, another N-1 times operations need to be performed which are similar to the above ones. It can be successfully realized with a certain probability which is determined by the product of the smaller coefficients of non-maximally entangled pairs. All possible unitary transformations are given in detail. 展开更多
关键词 arbitrary and unknown n-particle state probabilistic teleportation entanglement
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Atomic N00N state generation in distant cavities by virtual excitations 被引量:1
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作者 杨榕灿 李刚 +1 位作者 李杰 张天才 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第6期12-18,共7页
A general scheme of generating NOON states of virtually-excited 2N atoms is proposed. The two cavities are fibre-connected with N atoms in each cavity. Although we focus on the case of N = 2, the system can be extende... A general scheme of generating NOON states of virtually-excited 2N atoms is proposed. The two cavities are fibre-connected with N atoms in each cavity. Although we focus on the case of N = 2, the system can be extended to a few atoms with N 〉2. It is found that all 2N atoms can be entangled in the form of NOON states if the atoms in the first cavity are initially in the excited states and atoms in the second cavity are all in the ground states. The feasibility of the scheme is carefully discussed, it shows that the NOON state with a few atoms can be generated with good fidelity and the scheme is feasible in experiment. 展开更多
关键词 n00n states optical cavity optical fibre virtual excitations
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Teleportation of an Arbitrary Multipartite GHZ-Class State by One EPR Pair 被引量:3
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作者 王雅红 于长水 宋鹤山 《Chinese Physics Letters》 SCIE CAS CSCD 2006年第12期3142-3144,共3页
We present a scheme for perfectly teleporting an arbitrary and unknown N-particle GHZ-class state from a sender to a receiver. We just need one quantum channel composed of two or three particles in the maximally entan... We present a scheme for perfectly teleporting an arbitrary and unknown N-particle GHZ-class state from a sender to a receiver. We just need one quantum channel composed of two or three particles in the maximally entangled state. The sender performs one Bell-state measurement on two of her particles and N - 1 Hadamard operations and N - 1 yon Neumann measurements on the rest N - 1 particles. The receiver adopts one corresponding unitary transformation on his particles shared with the sender. After that, the receiver can obtain the original N-particle GHZ-class state by introducing N - 1 ancillary particles and carrying out N - 1 controlled-NOT operations. We also generalize the scheme to the case of controlled teleportation. 展开更多
关键词 n-PARTICLE state PROBABILISTIC TELEPORTATIOn 2-PARTICLE state EnTAnGLEDstate QUAnTUM state CHAnnELS
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融合Graph state LSTM与注意力机制的跨句多元关系抽取
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作者 衡红军 姚若男 《计算机应用与软件》 北大核心 2023年第8期214-220,290,共8页
已有的跨句多元关系抽取工作将输入文本表示为集成句内和句间依赖关系的复杂文档图,但图中包含的噪声信息会影响关系抽取的效果。针对这种情况,该文利用Graph state LSTM获得上下文信息,再分别利用词级注意力机制或位置感知的注意力机制... 已有的跨句多元关系抽取工作将输入文本表示为集成句内和句间依赖关系的复杂文档图,但图中包含的噪声信息会影响关系抽取的效果。针对这种情况,该文利用Graph state LSTM获得上下文信息,再分别利用词级注意力机制或位置感知的注意力机制,自动聚焦在对关系抽取起到决定性作用的关键词上,降低噪声信息的影响。并且比较了两种注意力机制对使用Graph state LSTM进行关系抽取的影响。通过在一个重要的精确医学数据集上进行实验,验证了该文所提出模型的有效性。 展开更多
关键词 跨句多元关系抽取 注意力机制 Graph state LSTM
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An Efficient Solid-State Synthesis of N-Aryl-2-phenyldiazenecarboxamides 被引量:2
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作者 Jian Ping LI Qian Fu LUO +2 位作者 Yi Yang SHEN Yu Lu WANG Hong WANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第2期107-108,共2页
A new and ancient solid-state reaction using K3Fe(CN)(6)/KOII to oxidize diaryl semicarbazides for preparing azo compounds has been reported. Nine N-aryl-2-phenyl-diazenecarboxamides have been synthesized in excellent... A new and ancient solid-state reaction using K3Fe(CN)(6)/KOII to oxidize diaryl semicarbazides for preparing azo compounds has been reported. Nine N-aryl-2-phenyl-diazenecarboxamides have been synthesized in excellent yields with simple instrument. 展开更多
关键词 Solid-state synthesis diaryl semicarbazide n-Aryl-2-phenyldiazenecarboxamide
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Generation of entangled coherent states through cavity-assisted interaction
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作者 陈晓东 顾永建 +2 位作者 梁鸿辉 倪彬彬 林秀敏 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第4期77-80,共4页
We propose schemes to generate an n-coherent-pulse GHZ state and a cluster state via the interaction between n coherent pulses and a two-sided cavity. In these schemes, a strong coupling condition is not needed, which... We propose schemes to generate an n-coherent-pulse GHZ state and a cluster state via the interaction between n coherent pulses and a two-sided cavity. In these schemes, a strong coupling condition is not needed, which makes the protocols possibly able to be implemented based on the current experiment technology. 展开更多
关键词 n-coherent-pulse GHZ state n-coherent-pulse cluster state two-sided cavities
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Generation of GHZ state and cluster state with atomic ensembles via the dipole-blockade mechanism
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作者 倪彬彬 顾永建 +3 位作者 陈晓东 梁鸿辉 林秀 林秀敏 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期168-172,共5页
This paper proposes scalable schemes to generate the Greenberger-Horne-Zeilinger (GHZ) state and the cluster state with atomic ensembles via the dipole blockade mechanism on an atom chip, where the qubit is not carr... This paper proposes scalable schemes to generate the Greenberger-Horne-Zeilinger (GHZ) state and the cluster state with atomic ensembles via the dipole blockade mechanism on an atom chip, where the qubit is not carried by a single atom but an atomic ensemble. In the protocols, multiqubit entangled states are determinately prepared. Needlessness for single-photon source further decreases the complexity of the experiment. Based on the present laboratory technique, the schemes may be realized. The achieved results reveal a prospect for large-scale quantum communication and quantum computation. 展开更多
关键词 Jipole-blockade mechanism n-qubit GHZ state n-qubit cluster
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A Single Photon Produces General W State of N 0ubits and Its Application
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作者 MEI Di LI Chong SONG He-Shan Department of Physics,Dalian University of Technology,Dalian 116023,China 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第7期75-78,共4页
Based on the Wu's scheme[C.F.Wu,J.L.Chen,L.C.Kwekl,and C.H.Ohel,Phys.Rev.A 73(2006)012310],we prepare the general N-qubit W state.We find that the concurrence of two qubits in general N-qubit Wstate is only relate... Based on the Wu's scheme[C.F.Wu,J.L.Chen,L.C.Kwekl,and C.H.Ohel,Phys.Rev.A 73(2006)012310],we prepare the general N-qubit W state.We find that the concurrence of two qubits in general N-qubit Wstate is only related to their coefficients and we successfully apply the general N-qubit W state to quantum state transferand quantum state prepare like that in two-qubit system. 展开更多
关键词 n-qubit W state COnCURREnCE quantum state transfer
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Scheme for probabilistic remotely preparing a multi-particle entangled GHZ state
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作者 马鹏程 詹佑邦 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期445-450,共6页
This paper presents a scheme for probabilistic remote preparation of a three-particle entangled Greenberger-Horne-Zeilinger (GHZ) state via three-particle orthonormal basis projective measurement, and then directly ... This paper presents a scheme for probabilistic remote preparation of a three-particle entangled Greenberger-Horne-Zeilinger (GHZ) state via three-particle orthonormal basis projective measurement, and then directly generalize the scheme to multi-particle case. It is shown that by using N pairs of bipartite non-maximally entangled states as the quantum channel and N-particle orthonormal basis projective measurement, the multi-particle remote preparation can be successfully realized with a certain probability. 展开更多
关键词 n-particle entangled GHZ state probabilistic remote state preparation n-particle projective measurement unitary transformation
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MRSDCI STUDIES OF LOW-LYING ELECTRONIC STATES OF THE N_2F^+ MOLECULE
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作者 Zheng Li CAI He Ming XIAO Department of Chemistry,East China Institute of Technology,Nanjing 210014 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第8期651-652,共2页
Ab initio electronic structure calculations are reported for low-lying electronic states,X ~1Σ^+and A ~1Π of the N_2F^+ molecule.Geometric parameters for the ground state X ~1Σ^+ are predicted by means of mul- tire... Ab initio electronic structure calculations are reported for low-lying electronic states,X ~1Σ^+and A ~1Π of the N_2F^+ molecule.Geometric parameters for the ground state X ~1Σ^+ are predicted by means of mul- tireference single and double excitation configuration interaction(MRSDCI)calculations with a double zeta plus polarization(DZ+P)basis set.Vertical excitation energy for these two electronic states is determined using MRSDCI/DZ+P calculations at the ground state equilibrium geometry.The oscillator strength for the X^1Σ+→ A ~1Π transition and the radiative lifetime for the A^1Π state are calculated based on the MRSDCI wavefunc- tions. 展开更多
关键词 MRSDCI STUDIES OF LOW-LYInG ELECTROnIC stateS OF THE n2F MOLECULE
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STATE TRANSFORMATION PROCESSES FOR FREE-FLOATING THREE-LINK PLANAR ROBOTS 被引量:1
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作者 XuMingtao XuYangsheng JamesK.Mills 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2004年第2期166-169,共4页
The transformation process of an m-DOF free-floating robot from one staticstate to a different static state has m degrees of freedom. The proposed approach of thesetransformations utilizes a series of single-DOF trans... The transformation process of an m-DOF free-floating robot from one staticstate to a different static state has m degrees of freedom. The proposed approach of thesetransformations utilizes a series of single-DOF transformation processes as an alternative to them-DOF transformation process. Two static state transformation processes are studied in detail.First, a single-DOF transformation process is established using a newly defined concept, referred toas transformation planning, and the definite integral of conservation of angular momentum. Second,the governing equation of the single-DOF transformation process is established using the dynamicequations of motion of the robot. This allows the joint torques to be computed to effect the statetransformation. Finally, an extension of the single-DOF transformation process is proposed to extendthe application of this proposed transformation methodology to create a transformation net whichallows the reconfiguration of a robot from one state to many other possible states. 展开更多
关键词 Planar robot Static state Single-DOF transformation process n-elementtransformation net
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Break Up of <i>N</i>-Soliton Bound State in a Gradient Refractive Index Waveguide with Nonlocal Nonlinearity
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作者 Isnani Darti Suhariningsih Suhariningsih +1 位作者 Marjono Marjono Agus Suryanto 《Optics and Photonics Journal》 2012年第3期178-184,共7页
We study the propagation of N-soliton bound state in a triangular gradient refractive index waveguide with nonlocal nonlinearity. The study is based on the direct numerical solutions of the model and subsequent eigenv... We study the propagation of N-soliton bound state in a triangular gradient refractive index waveguide with nonlocal nonlinearity. The study is based on the direct numerical solutions of the model and subsequent eigenvalues evolution of the corresponding Zakharov-Shabat spectral problem. In the waveguide with local nonlinearity, the velocity of a single soliton is found to be symmetric around zero and therefore the soliton oscillates periodically inside the waveguide. If the nonlocality is presence in the medium, the periodic motion of soliton is destroyed due to the soliton experiences additional positive acceleration induced by the nonlocality. In the waveguide with the same strength of nonlocality, a higher amplitude soliton experiences higher nonlocality effects, i.e. larger acceleration. Based on this soliton behavior we predict the break up of N-soliton bound state into their single-soliton constituents. We notice that the splitting process does not affect the amplitude of each soliton component. 展开更多
关键词 n-SOLITOn Bound state GRIn WAVEGUIDE nonlocal nonlinearity Conserved Implicit CRAnK-nICOLSOn Method Inverse Scattering Technique
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THE ■-STATE OF A SINGLE HOMOPOLYMER CHAIN IN SOLUTION
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作者 吴奇 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1999年第4期367-370,共4页
It has been an established practice to estimate the Θ-temperature of a polymer solution from thedisappearance of the interchain interactions (A_2 = 0) Recently, in studies of the temperature dependence ofthe chain co... It has been an established practice to estimate the Θ-temperature of a polymer solution from thedisappearance of the interchain interactions (A_2 = 0) Recently, in studies of the temperature dependence ofthe chain conformation in solution, we found that the change of the chain conformation clearly underwentthree different stages which could be viewed as the 'gas'. 'liquid' and 'solid' states in terms of the freedomof the 'blobs' on the chain. The transition temperature between the first and second stages corresponds nicelyto the Θ-temperature determined by the conventional method. It reveals, for the first time, that the Θ-temperature can be deduced from the conformation change of a single polymer chain in solution, which isimportant not only in conception, but also in practice. 展开更多
关键词 O-state Coil-to-globule transition Poly(n-isopropylacrylamide)
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非标准状态下NO_(3)-N在地表水水样中的保存方法研究
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作者 纪凯 邱海兵 +2 位作者 周佳 何彧 叶玉新 《当代化工研究》 2023年第7期167-169,共3页
样品采集是科学研究的主要手段,水样变化对数据分析的稳定有着重要意义。本研究参照目前使用较为普遍的保存方式,结合地表水水样NO_(3)-N浓度的变化原因,提出加酸保存、过滤保存以及加酸过滤三种方法,并通过设计实验观察不同保存方法的... 样品采集是科学研究的主要手段,水样变化对数据分析的稳定有着重要意义。本研究参照目前使用较为普遍的保存方式,结合地表水水样NO_(3)-N浓度的变化原因,提出加酸保存、过滤保存以及加酸过滤三种方法,并通过设计实验观察不同保存方法的保存效果,提出最优保存方法。实验研究表明得到过滤加酸可作为地表水测定NO_(3)-N的水样最佳保存方法,能保存到30天左右。 展开更多
关键词 非标准状态 nO_(3)-n 保存方法 过滤 加酸
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基于M/M/1/N/∞排队模型的低功耗输电铁塔组立监测系统
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作者 张龙斌 刘少波 +2 位作者 唐波 尚智宇 刘思煜 《电子测量技术》 北大核心 2023年第14期66-72,共7页
传统输电铁塔组立监测系统存在无效能耗的数据传输空闲状态,致使其续航时间难以满足实际工程需求。为此,本文基于将空闲时间段的传感器转为低功耗休眠状态的思想,提出了一种适用于输电铁塔组立监测系统数据传输的M/M/1/N/∞排队模型,推... 传统输电铁塔组立监测系统存在无效能耗的数据传输空闲状态,致使其续航时间难以满足实际工程需求。为此,本文基于将空闲时间段的传感器转为低功耗休眠状态的思想,提出了一种适用于输电铁塔组立监测系统数据传输的M/M/1/N/∞排队模型,推导了监测系统中数据传输的分布方程,通过求解监测数据等待队长与有效输入率的比值和确定对应的数据传输轮换次数,确定了各传感器的数据传输空闲时间,实现了将处于空闲时间段的传感器转为休眠状态的低功耗工作模式。据此方法,研制的输电铁塔组立监测系统在周宁~宁德500 kV线路工程6天的实际监测过程中共耗电24%,续航时间与传统方法相比提升了1.9倍,满足监测系统续航时间大于单基铁塔组立施工周期的工程需求。 展开更多
关键词 输电铁塔组立监测系统 M/M/1/n/∞排队模型 数据传输空闲时间 休眠状态
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多模奇相干态光场中的N-Y最小测不准态与N-H最小测不准态 被引量:55
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作者 许定国 侯瑶 +1 位作者 杨志勇 侯洵 《光子学报》 EI CAS CSCD 1999年第7期577-587,共11页
本文根据新近建立的多模辐射场的广义非线性等阶高阶压缩理论,对多模奇相干态光场|Ψ,o〉q中的N次方Y压缩、N次方H压缩、N-Y最小测不准态以及N-H最小测不准态等进行了详细研究.结果表明:1)当压缩阶数N为偶数时,多... 本文根据新近建立的多模辐射场的广义非线性等阶高阶压缩理论,对多模奇相干态光场|Ψ,o〉q中的N次方Y压缩、N次方H压缩、N-Y最小测不准态以及N-H最小测不准态等进行了详细研究.结果表明:1)当压缩阶数N为偶数时,多模奇相干态|Ψ,o〉q总是恒处于N-Y最小测不准态;当N为奇数时,态|Ψ,o〉q既不处于N-Y最小测不准态,也不呈现N次方Y压缩效应.2)当q·N为偶数时,多模奇相干态|Ψ,o〉q总是恒处于N-H最小测不准态;当q·N为奇数时,态|Ψ,o〉q既不处于N-H最小测不准态,也不呈现N次方H压缩效应.3)多模奇相干态|Ψ,o〉q恒处于N-Y最小测不准态与恒处于N-H最小测不准态的条件明显不同。 展开更多
关键词 多模奇相干态 n-Y 最小测不准态 n-H 光场
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一种新型的两态叠加多模Schrdinger猫态光场的等阶N次方Y压缩 被引量:41
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作者 刘伟民 侯瑶 +2 位作者 杨志勇 孙秀泉 侯洵 《光子学报》 EI CAS CSCD 1999年第10期869-882,共14页
本文根据量子力学的线性叠加原理,构造了由多模(即q模时目平态的相反态|{{-Zj}〉q及多模虚相干态|{{-Zj}〉q这两者的线性叠加所组成的一种新型的多模Schrodinger猫态光场利用新近建立的多模压缩态理论,研究了态的N次方Y压缩... 本文根据量子力学的线性叠加原理,构造了由多模(即q模时目平态的相反态|{{-Zj}〉q及多模虚相干态|{{-Zj}〉q这两者的线性叠加所组成的一种新型的多模Schrodinger猫态光场利用新近建立的多模压缩态理论,研究了态的N次方Y压缩效应,结果发现:①当压缩阶数N=Zp且p=2m(m=1,2,3,…,…)时,态。总是恒处于N-Y最小测不准态;②当压缩阶数N=2p且p=2m+1(m=0,1,2,3,…,…)时,如果各模的初始相位,态间的初始相位差以及各单模相干态光场的平均光子数之总和等满足一定的量子化条件,则态可呈现出周期性变化的、任意阶的N次方Y压缩效应;③当压缩阶数N=2P'+1时,无论p'=2m(m=0,1,2,…,…)还是p'=2m+1(m=0,1,2,3,…,……),只要各模的初始相位满足一定的量子条件,则当两态叠加几率幅满足时,态就恒处于N-Y测不准态,始终不呈现N-Y最小测不准态和N次方Y压缩;而当时,态始终不呈现N-Y测不准态、N-Y最小测不准态和N次方Y压缩效应. 展开更多
关键词 两态叠加 多模 S-猫态 n次方Y压缩 光场
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