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Nonstandard Unitary Transformations of Quantum States
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作者 Gombojav O. Ariunbold 《Journal of Applied Mathematics and Physics》 2023年第9期2568-2575,共8页
In quantum optics, unitary transformations of arbitrary states are evaluated by using the Taylor series expansion. However, this traditional approach can become cumbersome for the transformations involving non-commuti... In quantum optics, unitary transformations of arbitrary states are evaluated by using the Taylor series expansion. However, this traditional approach can become cumbersome for the transformations involving non-commuting operators. Addressing this issue, a nonstandard unitary transformation technique is highlighted here with new perspective. In a spirit of “quantum” series expansions, the transition probabilities between initial and final states, such as displaced, squeezed and other nonlinearly transformed coherent states are obtained both numerically and analytically. This paper concludes that, although this technique is novel, its implementations for more extended systems are needed. 展开更多
关键词 Taylor Series unitary transformation Temporal Evolution Displaced State Coherent State Squeezed State Two-Mode Squeezed State Holstein-Primakoff State
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Unitary Transformation in Quantum Teleportation
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作者 WANG Zheng-Chuan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期857-858,共2页
In the well-known treatment of quantum teleportation, the receiver should convert the state of his EPR particle into the replica of the unknown quantum state by one of four possible unitary transformations. However, t... In the well-known treatment of quantum teleportation, the receiver should convert the state of his EPR particle into the replica of the unknown quantum state by one of four possible unitary transformations. However, the importance of these unitary transformations must be emphasized. We will show in this paper that the receiver cannot transform the state of his particle into an exact replica of the unknown state which the sender wants to transfer if he has not a proper implementation of these unitary transformations. In the procedure of converting state, the inevitable coupling between EPR particle and environment which is needed by the implementation of unitary transformations will reduce the accuracy of the replica. 展开更多
关键词 quantum telepertation EPR particle unitary transformation
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Matrix Tensor Product Approach to the Equivalence of Multipartite States under Local Unitary Transformations
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作者 GAO Xiu-Hong S. Alberverio +1 位作者 FEI Shao-Ming WANG Zhi-Xi 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第2期267-270,共4页
The equivalence of multipartite quantum mixed states under local unitary transformations is studied. A criterion for the equivalence of non-degenerate mixed multipartite quantum states under local unitary transformati... The equivalence of multipartite quantum mixed states under local unitary transformations is studied. A criterion for the equivalence of non-degenerate mixed multipartite quantum states under local unitary transformations is presented. 展开更多
关键词 local unitary transformation multipartite quantum mixed state tensor decomposable
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Unitary transformation of general nonoverlapping-image multimode interference couplers with any input and output ports
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作者 Ze-Zheng Li Wei-Hua Han Zhi-Yong Li 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第1期287-292,共6页
An explanation of optical unitary transformation is presented for general nonoverlapping-image multimode interference(MMI)couplers with any number of input and output ports.The light transformation in the MMI coupler ... An explanation of optical unitary transformation is presented for general nonoverlapping-image multimode interference(MMI)couplers with any number of input and output ports.The light transformation in the MMI coupler can be considered as an optical field matrix acting on an input light column vector.We investigate the general phase principle of output light image.The complete proof of nonoverlapping-image MMI coupler’s optical unitarity along with the phase analysis of matrix element is provided.Based on a two-dimensional finite-difference time-domain(2 D-FDTD)simulation,the unitary transformation is obtained for a 4×4 nonoverlapping-image MMI coupler within a deviation of 4×10-2 for orthogonal invariance and 8×10-2 for transvection invariance in the C-band spectral range.A compact 1×4 splitter based on cascaded MMI coupler is proposed,showing a phase deviation less than 5.4°while maintaining a low-loss performance in C-band spectra. 展开更多
关键词 multimode interference coupler optical unitary transformation integrated photonics
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Unitary Transformation in kq Representation
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作者 YANG Zhan-Ying ZHANG Kai +1 位作者 HOU Bo-Yu SHI Kang-Jie 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第7期103-107,共5页
In this paper,we discuss the unitary transformation induced by Z_6 rotations of noncommutative space onthe states |k,q,s〉,which plays a key role in construction for noncommutative solitons T^2/Z_6 by GHS method.As ar... In this paper,we discuss the unitary transformation induced by Z_6 rotations of noncommutative space onthe states |k,q,s〉,which plays a key role in construction for noncommutative solitons T^2/Z_6 by GHS method.As aresult,we prove a well-known 'Gauss Sum' formula in the number theory through a concise way. 展开更多
关键词 unitary transformation kq representation
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Quantum Systems Connected by a Time-Dependent Canonical Transformation
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作者 Kyu Hwang Yeon Jeong Ryeol Choi ZHANG Shou 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第9期416-420,共5页
We study both classical and quantum relation between two Hamiltonian systems which are mutually connected by time-dependent canonical transformation. One is ordinary conservative system and the other is timedependent ... We study both classical and quantum relation between two Hamiltonian systems which are mutually connected by time-dependent canonical transformation. One is ordinary conservative system and the other is timedependent Hamiltonian system. The quantum unitary operator relevant to classical canonical transformation between the two systems are obtained through rigorous evaluation. With the aid of the unitary operator, we have derived quantum states of the time-dependent Hamiltonian system through transforming the quantum states of the conservative system. The invariant operators of the two systems are presented and the relation between them are addressed. We showed that there exist numerous Hamiltonians, which gives the same classical equation of motion. Though it is impossible to distinguish the systems described by these Hamiltonians within the realm of classical mechanics, they can be distinguishable quantum mechanically. 展开更多
关键词 canonical transformation innumerable kind of Hamiltonians canonical quantization invariant operator unitary transformation
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Gradient Transformation of Momentum and Single-Valued Vector Potential in Nonrelativistic Dynamics
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作者 Illia Dubrovskyi 《Journal of Physical Science and Application》 2014年第5期328-332,共5页
A vector potential of a magnetic field in Lagrangian is defined as the necessary partial solution of a inhomogeneous differential equation. The "gradient transformation" is an addition of arbitrary general solution ... A vector potential of a magnetic field in Lagrangian is defined as the necessary partial solution of a inhomogeneous differential equation. The "gradient transformation" is an addition of arbitrary general solution of the corresponding homogeneous equation that does not change the Lagrange equations. When dynamics is described by momenta and coordinates, this transformation is not the vector potential modification, which does not change expressions for other physical quantities, but a canonical transformation of momentum, which changes expressions for all fimctions of momentum, not changing the Poisson brackets, and, hence, the integrals of motion. The generating function of this transformation must reverse sign under the time-charge reversal. In quantum mechanics the unitary transformation corresponds to this canonical transformation. It also does not change the commutation relations. The phase of this unitary operator also must reverse sign under the time-charge reversal. Examples of necessary vector potentials for some magnetic fields are presented. 展开更多
关键词 Magnetic field vector potential MOMENTUM gradient transformation canonical transformation unitary transformation.
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Real-domain GMUSIC algorithm based on unitary-transform for low-angle estimation 被引量:1
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作者 Zheng Liu Yuanyuan Wang Yunhe Cao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第5期794-799,共6页
In order to realize the elevation angle estimation for low-altitude targets at a low computational cost, a generalized multiple signal classification (GMUSIC) algorithm based on unitary transform is proposed, i.e., ... In order to realize the elevation angle estimation for low-altitude targets at a low computational cost, a generalized multiple signal classification (GMUSIC) algorithm based on unitary transform is proposed, i.e., the DU-GMUSlC algorithm. Firstly, the covariance matrix of received data is used to construct the Centro- Hermitian matrix. Then, the real-domain GMUSIC algorithm is used to implement the initial angle estimation, and the multipath attenuation coefficient is calculated in succession. Finally, the attenuation coefficient is taken into account in the GMUSIC method to carry out the secondary angle estimation which is beneficial to further improvement of the angle estimation accuracy. This method can meet requirements of low-angle accuracy as well as lower computational burden. Simulation results prove the correctness and effectiveness of the proposed algorithm. Moreover, field experiment data are used to further validate the effectiveness of this method. 展开更多
关键词 multipath effect low-angle estimation unitary transform. attenuation coefficient.
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Probabilistic teleportation of an arbitrary three-particle state 被引量:13
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作者 林秀 李洪才 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第9期1724-1731,共8页
A scheme for teleporting an arbitrary and unknown three-particle state from a sender to either one of two receivers is proposed. The quantum channel is composed of a two-particle non-maximally entangled state and two ... A scheme for teleporting an arbitrary and unknown three-particle state from a sender to either one of two receivers is proposed. The quantum channel is composed of a two-particle non-maximally entangled state and two three-particle non-maximally entangled W states. An arbitrary three-particle state can be perfectly teleported probabilistically if the sender performs three generalized Bell-state measurements and sends to the two receivers the classical result of these measurements, and either one of the two receivers adopts an appropriate unitary transformation conditioned on the suitable measurement outcomes of the other receiver. All kinds of unitary transformations are given in detail. 展开更多
关键词 probabilistic teleportation arbitrary three-particle state unitary transformation three-particle entangled W state
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Teleportation of an Arbitrary Three-Particle State via Three EPR Pairs 被引量:8
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作者 FANGJian-Xing ZHUShi-Qun CHENXian-Feng ZHANGRong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期369-372,共4页
A scheme of teleportation of an arbitrary three-particle state is presented when three pairs of entangled particles are used as quantum channels. After the Bell state measurements are operated by the sender, the origi... A scheme of teleportation of an arbitrary three-particle state is presented when three pairs of entangled particles are used as quantum channels. After the Bell state measurements are operated by the sender, the original state with deterministic probability can be reconstructed by the receiver when a corresponding unitary transformation is followed. 展开更多
关键词 TELEPORTATION arbitrary three-particle state three-entangled particle pairs unitary transformation
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Probabilistic teleportation of multi-particle partially entangled state 被引量:6
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作者 陈秀波 杜建忠 +1 位作者 温巧燕 朱甫臣 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第3期771-777,共7页
Utilizing the generalized measurement described by positive operator-wlued measure, this paper comes up with a protocol for teleportation of an unknown multi-particle entangled (GHZ) state with a certain probability... Utilizing the generalized measurement described by positive operator-wlued measure, this paper comes up with a protocol for teleportation of an unknown multi-particle entangled (GHZ) state with a certain probability. The feature of the present protocol is to weaken requirement for the quantum channel initially shared by sender and receiver. All unitary transformations performed by receiver are summarized into a formula. On the other hand, this paper explicitly constructs the efficient quantum circuits for implementing the proposed teleportation by means of universal quantum logic operations in quantum computation. 展开更多
关键词 quantum teleportation quantum circuits positive operator-valued measure unitary transformations
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Teleportation of an Arbitrary Two-Particle State by Two Partial Entangled Three-Particle GHZ States 被引量:6
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作者 DAIHong-Yi CHENPing-Xing LICheng-Zu 《Communications in Theoretical Physics》 SCIE CAS CSCD 2005年第5期799-802,共4页
We present a scheme for teleporting an unknown arbitrary two-particle state from a sender to either one of two receivers. The quantum channel is composed of two partial entangled three-particle GHZ states. An unknown ... We present a scheme for teleporting an unknown arbitrary two-particle state from a sender to either one of two receivers. The quantum channel is composed of two partial entangled three-particle GHZ states. An unknown arbitrary two-particle state can be perfectly teleported probabilistically if the sender performs two generalized Bell-state measurements and each receiver introduces an appropriate unitary transformation with the help of the other receiver's Hadamard operations and simple measurements. 展开更多
关键词 probabilistic teleportation arbitrary two-particle state unitary transformation Hadamard operation
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Teleportation of a Three—Particle state via Entanglement Swapping 被引量:5
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作者 FANGJian-Xing LINGYin-Sheng ZHUShi-Qun CHENXian-Feng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第5期529-530,共2页
A scheme for teleporting a three-particle state is proposed when three pairs of entangled particles are used as quantum channel. After a sender operates the Bell-state measurement, the original state with deterministi... A scheme for teleporting a three-particle state is proposed when three pairs of entangled particles are used as quantum channel. After a sender operates the Bell-state measurement, the original state with deterministic probability can be reconstructed when the receiver performs a corresponding measurement with unitary transformation. 展开更多
关键词 TELEPORTATION three-particle state entanglement swapping unitary transformation
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Probabilistic Teleportation of an Arbitrary Two-Particle State and Its Quantum Circuits 被引量:5
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作者 GUO Zhan-Ying FANG Jian-Xing +1 位作者 ZHU Shi-Qun QIAN Xue-Min 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第6期1013-1017,共5页
Two simple schemes for probabilistic teleportation of an arbitrary unknown two-particle state using a non-maximally entangled EPR pair and a non-maximally entangled GHZ state as quantum channels are proposed. After re... Two simple schemes for probabilistic teleportation of an arbitrary unknown two-particle state using a non-maximally entangled EPR pair and a non-maximally entangled GHZ state as quantum channels are proposed. After receiving Alice's Bell state measurement results, Bob performs a collective unitary transformation on his inherent particles without introducing the auxiliary qubit. The original state can be probabilistically teleported. Meanwhile, quantum circuits for realization of successful teleportation are also presented. 展开更多
关键词 probabilistic teleportation arbitrary two-particle state unitary transformation quantum circuit
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Probabilistic teleportation of a non-symmetric three-particle state 被引量:4
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作者 陈秀波 温巧燕 朱甫臣 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第10期2240-2245,共6页
This paper proposes a scheme for teleporting a kind of essential three-particle non-symmetric entangled state, which is much more valuable than a GHZ and W state for some applications in quantum information processing... This paper proposes a scheme for teleporting a kind of essential three-particle non-symmetric entangled state, which is much more valuable than a GHZ and W state for some applications in quantum information processing. In comparison with previous proposal of teleportation, the resources of entangled states as quantum channel and the number of classical messages required by our scheme can be cut down. Moreover, it is shown that there exists a class of transformations which ensure the success of this scheme, because the two-particle transformation performed by the receiver in the course of teleportation may be a generic two-particle operation instead of a control-NOT (CNOT) operation. In addition, all kinds of transformations performed by sender and receiver are given in detail. 展开更多
关键词 probabilistic teleportation three-particle entangled state non-maximally entangled state unitary transformation
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Remote Preparation of a Two-Particle Entangled State by a Bipartite Entangled State and a Tripartite Entangled W State 被引量:4
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作者 XIAO Xiao-Qi LIU Jin-Ming 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2期247-252,共6页
We propose a scheme to remotely prepare a general two-particle entangled state by using a bipartite entangled state and a tripartite entangled W state as the quantum channel. Our scheme consists of one sender and two ... We propose a scheme to remotely prepare a general two-particle entangled state by using a bipartite entangled state and a tripartite entangled W state as the quantum channel. Our scheme consists of one sender and two remote receivers. The sender can help either one of the receivers to remotely reconstruct the original state with the assistance of the other receiver's single-partlcle orthogona/measurement. We obtain the total success probability and discuss the classical communication cost in our remote state preparation scheme. 展开更多
关键词 remote state preparation W state projective measurement unitary transformation
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Controlled Teleportation of an Arbitrary Two-Particle State by One EPR Pair and Cluster State 被引量:3
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作者 郭战营 尚晓星 +1 位作者 方建兴 肖瑞华 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第11期819-823,共5页
A scheme for controlled teleportation of an arbitrary two-particle state using a maximally entangled EPR pair and a cluster state as the quantum channel is proposed. After receiving Alice's Bell state measurement res... A scheme for controlled teleportation of an arbitrary two-particle state using a maximally entangled EPR pair and a cluster state as the quantum channel is proposed. After receiving Alice's Bell state measurement results, the controller performs a joint measurement on his particles under a non-maximally entangled Bell-basis. The receiver needs to introduce an auxiliary qubit, and performs a series of appropriate unitary transformations on his particles. The original state can be teleported successfully with the probability 2 cos2θ. 展开更多
关键词 controlled teleportation arbitrary two-particle state cluster state unitary transformation
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Controlled Quantum Teleportation of a One-Particle Unknown State via a Three-Particle Entangled State 被引量:3
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作者 XIU Xiao-Ming DONG Li GAO Ya-Jun CHI Feng 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第2X期261-263,共3页
A kind of three-particle entangled state is applied as quantum channel of the controlled quantum teleporration of a one-particle unknown state. The one-particle unknown state is transmitted from the sender to the reci... A kind of three-particle entangled state is applied as quantum channel of the controlled quantum teleporration of a one-particle unknown state. The one-particle unknown state is transmitted from the sender to the recipient under the control of the supervisor. After the sender makes Bell-state measurement and the supervisor performs von Neumann measurement, the recipient carries out unitary transformation on his own particle depending on classical information from the sender and the supervisor. The teleportation cannot be completed successfully by the recipient if the supervisor does not agree to cooperate. The roles of the recipient and the supervisor may be exchanged in this scheme. The scheme is flexible and feasible because the sequence of manipulation of the sender and the supervisor may be exchanged and only simple unitary transformation is included. 展开更多
关键词 quantum information controlled quantum teleportation ENTANGLEMENT unitary transformation
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Generation of the nonlocal quantum entanglement of three three-level particles by local operations 被引量:2
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作者 金星日 张英俏 +1 位作者 金哲 张寿 《Chinese Physics B》 SCIE EI CAS CSCD 2005年第10期1936-1941,共6页
We propose a scheme to realize the nonlocal quantum entanglement of three three-level particles by using a threeparticle entangled state of three levels as a quantum channel with the aid of some local unitary transfor... We propose a scheme to realize the nonlocal quantum entanglement of three three-level particles by using a threeparticle entangled state of three levels as a quantum channel with the aid of some local unitary transformations. This scheme can be directly generalized to the nonlocal quantum entanglement of N three-level particles. 展开更多
关键词 quantum entanglement three-level particle unitary transformation
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Multi-party dense coding in non-symmetric quantum channel 被引量:2
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作者 付长宝 夏岩 张寿 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第8期1682-1685,共4页
A three- and an (N+ 1)-party dense coding scheme in the case of non-symmetric Hilbert spaces of the particles of a quantum channel are investigated by using a multipartite entangled state. In the case of the (N ... A three- and an (N+ 1)-party dense coding scheme in the case of non-symmetric Hilbert spaces of the particles of a quantum channel are investigated by using a multipartite entangled state. In the case of the (N + 1)-party dense coding scheme, we show that the amount of classical information transmitted from N senders to one receiver is improved. 展开更多
关键词 non-symmetric Hilbert space dense coding unitary transformation
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