In this paper, we propose a physical scheme to realize quantum SWAP gate by using a large-detuned single-mode cavity field and two identical Rydberg atoms. It is shown that the scheme can also be used to create multi-...In this paper, we propose a physical scheme to realize quantum SWAP gate by using a large-detuned single-mode cavity field and two identical Rydberg atoms. It is shown that the scheme can also be used to create multi-atom cluster state. During the interaction between atom and cavity, the cavity is only virtually excited and thus the scheme is insensitive to the cavity field states and cavity decay. With the help of our scheme it is very simple to prepare the N-atom cluster state with perfect fidelity and probability. The practical feasibility of this method is also discussed.展开更多
This paper proposes a simple scheme to generate a four-atom entangled cluster state in cavity quantum electrodynamics. With the assistantce of a strong classical field the cavity is only virtually excited and no quant...This paper proposes a simple scheme to generate a four-atom entangled cluster state in cavity quantum electrodynamics. With the assistantce of a strong classical field the cavity is only virtually excited and no quantum information will be transferred from the atoms to the cavity during the preparation for a four-atom entangled cluster state, and thus the scheme is insensitive to the cavity field states and cavity decay. Assuming that deviation of laser intensity is 0.01 and that of simultaneity for the interaction is 0.01, it shows that the fidelity of the resulting four-atom entangled cluster state is about 0.9886. The scheme can also be used to generate a four-ion entangled cluster state in a hot trapped-ion system. Assuming that deviation of laser intensity is 0.01, it shows that the fidelity of the resulting four-ion entangled cluster state is about 0.9990. Experimental feasibility for achieving this scheme is also discussed.展开更多
We propose a scheme to achieve a kind of nontrivial multipartite pair-wise controlled phase operation in a cavity QED setup. The operation implemented is of geometrical nature and is not sensitive to the thermal state...We propose a scheme to achieve a kind of nontrivial multipartite pair-wise controlled phase operation in a cavity QED setup. The operation implemented is of geometrical nature and is not sensitive to the thermal state of the cavity. In particular, we have managed to avoid the conventional dispersive coupling so that high speed gate operation is achieved which is very important in view of decoherence. We show that this multipartite pair-wise controlled phase operation makes the generation of two-dimensional cluster states very efficient.展开更多
We propose an experimentally feasible scheme for preparing a four-atom cluster state in a thermal cavity. In the scheme, the cavity field is only virtually excited and the photon-number-dependent part in the effective...We propose an experimentally feasible scheme for preparing a four-atom cluster state in a thermal cavity. In the scheme, the cavity field is only virtually excited and the photon-number-dependent part in the effective Hamiltonian is cancelled so that the system is insensitive to the cavity decay and the thermal field. At the same time, the scheme can be generalized to prepare n-atom cluster states with the success probability 100%. In addition, using the four-atom cluster state, we also propose a simpler scheme for implementing a remote-controlled not gate (CNOT) without the Bell states measurement.展开更多
This paper proposes a scalable scheme to generate n-atom GHZ states and cluster states by using the basic building block, i.e., a weak coherent optical pulse [α) being reflected successively from a single-atom cavit...This paper proposes a scalable scheme to generate n-atom GHZ states and cluster states by using the basic building block, i.e., a weak coherent optical pulse [α) being reflected successively from a single-atom cavity. In the schemes, coherent state of light is used instead of single photon source, homodyne measurement on coherent light is done kastead of single photon detection, and no need for individually addressing keeps the schemes easy to implement from the experimental point of view. The successful probabilities of our protocols approach unity in the ideal case.展开更多
我们为认识到量纠纷在洞证完在原子之间交换建议一个计划。与洞的仅仅虚拟的刺激在在原子和洞之间的相互作用期间,计划对洞模式状态和洞腐烂感觉迟钝。Theideas 能也为认识到纠纷处于 W 状态处于钟状态和原子层次处于钟状态并且在原子...我们为认识到量纠纷在洞证完在原子之间交换建议一个计划。与洞的仅仅虚拟的刺激在在原子和洞之间的相互作用期间,计划对洞模式状态和洞腐烂感觉迟钝。Theideas 能也为认识到纠纷处于 W 状态处于钟状态和原子层次处于钟状态并且在原子层次之间在一个单个原子和原子层次在原子层次之间交换被利用。展开更多
We propose the methods of generating multipartite entanglement by considering the interaction of a system of N two-level atoms in M cavities of high quality factor with a strong classical driving field. It is shown th...We propose the methods of generating multipartite entanglement by considering the interaction of a system of N two-level atoms in M cavities of high quality factor with a strong classical driving field. It is shown that, with the cavity detuning, the applied driving field detuning and vacuum Rabi coupling, we can produce an entangled coherent state in two single-mode cavities and generate the entangled coherent cluster states in two bimodal vacuum cavities. Tuning these parameters also allows us to acquire the anti-Jaynes-Cummings (AJC) interaction, with which we can generate the maximally two-photon entangled states, and the two-atom and the two-photon entangled cluster states.展开更多
We outline a scheme for entanglement swapping based on cavity QED as well as quasi-Bell state measurement(quasiBSM) methods. The atom–field interaction in the cavity QED method is performed in small and large detunin...We outline a scheme for entanglement swapping based on cavity QED as well as quasi-Bell state measurement(quasiBSM) methods. The atom–field interaction in the cavity QED method is performed in small and large detuning regimes.We assume two atoms are initially entangled together and, distinctly two cavities are prepared in an entangled coherent–coherent state. In this scheme, we want to transform entanglement to the atom-field system. It is observed that, the fidelities of the swapped entangled state in the quasi-BSM method can be compatible with those obtained in the small and large detuning regimes in the cavity QED method(the condition of this compatibility will be discussed). In addition, in the large detuning regime, the swapped entangled state is obtained by detecting and quasi-BSM approaches. In the continuation,by making use of the atom–field entangled state obtained in both approaches in a large detuning regime, we show that the atomic as well as field states teleportation with complete fidelity can be achieved.展开更多
A scheme is proposed to generate an N-qubit cluster-type entangled squeezed vacuum state (CTESVS) based on the two-photon interaction between a two-level atomand the cavity fields with the cavity QED system. The CTE...A scheme is proposed to generate an N-qubit cluster-type entangled squeezed vacuum state (CTESVS) based on the two-photon interaction between a two-level atomand the cavity fields with the cavity QED system. The CTESVS in N separate cavities can be effectively obtained after performing a simple one-qubit measurement on the atom. The influence of cavity decay on the CTESVS is also discussed.展开更多
This paper proposes schemes for generating multiple-photon and multiple-atom cluster states, respectively. The schemes are based on the cavity input-output process and atomic or photonic states measurement, and the su...This paper proposes schemes for generating multiple-photon and multiple-atom cluster states, respectively. The schemes are based on the cavity input-output process and atomic or photonic states measurement, and the successful probabilities approach unity in the ideal case. The numerical simulations show that the produced multiple-particle cluster states have high fidelity even if the Lamb-Dicke condition is not satisfied. Some practical imperfections, such as atomic spontaneous emission and output coupling inefficiency, only decrease the success probability but exert no influence on the fidelity of generated multiple-particle cluster states. From the experimental point of view, smaller operation number and lack of need for individual addressing keeps the schemes easy to implement. These schemes may offer a promising approach to the generation of a large-scale cluster state.展开更多
Schemes are presented for realizing quantum controlled phase gate and preparing an N-qubit W-like state, which are based on the large-detuned interaction among three-state atoms, dual-mode cavity and a classical pulse...Schemes are presented for realizing quantum controlled phase gate and preparing an N-qubit W-like state, which are based on the large-detuned interaction among three-state atoms, dual-mode cavity and a classical pulse. In particular, a class of W states that can be used for perfect teleportation and superdense coding is generated by only one step. Compared with the previous schemes, cavity decay is largely suppressed because the cavity is only virtually excited and always in the vacuum state and the atomic spontaneous emission is strongly restrained due to a large atom-field detuning.展开更多
We present an efficient scheme for undeniable five-party quantum state sharing(FQSTS) of an arbitrary single-atom state with a five-atom cluster state in cavity QED.The implementation of this scheme does not involve t...We present an efficient scheme for undeniable five-party quantum state sharing(FQSTS) of an arbitrary single-atom state with a five-atom cluster state in cavity QED.The implementation of this scheme does not involve the joint-state measurement of multi-atoms,which makes it convenient in a practical application.The scheme is also insensitive to the cavity decay and the thermal field.展开更多
We propose an experimentally feasible protocol for implementing controlled dense coding with a six-atom cluster state in cavity QED. In the scheme, we investigate that the atoms interact simultaneously with the highly...We propose an experimentally feasible protocol for implementing controlled dense coding with a six-atom cluster state in cavity QED. In the scheme, we investigate that the atoms interact simultaneously with the highly detuned single-mode cavity and the strong classical driving field, and thus our scheme is not sensitive to both the cavity decay and the thermal field. In addition, the four-atom entangled states can be exactly distinguished by performing the single-atom measurements in cavity QED, therefore our scheme might be implemented in a simple way.展开更多
An experimentally realizable physical scheme for preparing multiqubit cluster states from a large detuned atomcavity interaction is proposed. The scheme is free of any type of measurement and insensitive to the cavity...An experimentally realizable physical scheme for preparing multiqubit cluster states from a large detuned atomcavity interaction is proposed. The scheme is free of any type of measurement and insensitive to the cavity decay, and the cavity field is only virtually excited so that there is no information exchanging between atom and cavity. The time required for the gate operations is very short, which is important for decoherence. We also discuss the experimental feasibility of our scheme.展开更多
This paper proposes a scheme where entanglement swapping between atom and cavity can be realized. A-type three-level atoms interacting resonantly with cavity field are considered. By detecting atom and cavity field, i...This paper proposes a scheme where entanglement swapping between atom and cavity can be realized. A-type three-level atoms interacting resonantly with cavity field are considered. By detecting atom and cavity field, it realizes entanglement swapping between atom and cavity. It uses the technique of entanglement swapping to generate an entangled state of two cavity fields by measuring on atoms. It discusses the experimental feasibility of the proposed scheme and application of entangled state of cavity fields.展开更多
We propose a scheme to generate atomic cluster states of arbitrary configuration in the cavity quantumelectrodynamics (QED) system.The process is achieved via adiabatic evolution of dark states,which only requiresadia...We propose a scheme to generate atomic cluster states of arbitrary configuration in the cavity quantumelectrodynamics (QED) system.The process is achieved via adiabatic evolution of dark states,which only requiresadiabatically increasing or decreasing Rabi frequencies of laser.Thus it allows the robust implementation of entanglementagainst certain types of errors.Our scheme is relatively decoherence-free in the sense that excited atomic states are neverpopulated and excited cavity photon states can be made negligible in certain conditions.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant No 10374025)Major Project supported by the Ministry of Education of Hunan Province, China (Grant No 06A038)
文摘In this paper, we propose a physical scheme to realize quantum SWAP gate by using a large-detuned single-mode cavity field and two identical Rydberg atoms. It is shown that the scheme can also be used to create multi-atom cluster state. During the interaction between atom and cavity, the cavity is only virtually excited and thus the scheme is insensitive to the cavity field states and cavity decay. With the help of our scheme it is very simple to prepare the N-atom cluster state with perfect fidelity and probability. The practical feasibility of this method is also discussed.
基金Project supported by the Postdoctal Foundation of Central South University of Chinathe Important Program of Hunan Provincial Education Department of China (Grant No. 06A038)+1 种基金Department of Education of Hunan Province of China (Grant No. 06C080)Hunan Provincial Natural Science Foundation,China (Grant No. 07JJ3013)
文摘This paper proposes a simple scheme to generate a four-atom entangled cluster state in cavity quantum electrodynamics. With the assistantce of a strong classical field the cavity is only virtually excited and no quantum information will be transferred from the atoms to the cavity during the preparation for a four-atom entangled cluster state, and thus the scheme is insensitive to the cavity field states and cavity decay. Assuming that deviation of laser intensity is 0.01 and that of simultaneity for the interaction is 0.01, it shows that the fidelity of the resulting four-atom entangled cluster state is about 0.9886. The scheme can also be used to generate a four-ion entangled cluster state in a hot trapped-ion system. Assuming that deviation of laser intensity is 0.01, it shows that the fidelity of the resulting four-ion entangled cluster state is about 0.9990. Experimental feasibility for achieving this scheme is also discussed.
基金Project supported by the National Fundamental Research Program of China (Grant No. 2013CB921804)the National Natural Science Foundation of China(Grant No. 11004065)+1 种基金the Natural Science Foundation of Guangdong Province of China (Grant Nos. 10451063101006312 and S2011040000403)the Funds of the Education Department of Anhui Province of China (Grant Nos. KJ2010A323, 2010SQRL187, and KJ2012B075)
文摘We propose a scheme to achieve a kind of nontrivial multipartite pair-wise controlled phase operation in a cavity QED setup. The operation implemented is of geometrical nature and is not sensitive to the thermal state of the cavity. In particular, we have managed to avoid the conventional dispersive coupling so that high speed gate operation is achieved which is very important in view of decoherence. We show that this multipartite pair-wise controlled phase operation makes the generation of two-dimensional cluster states very efficient.
基金Project supported by the National Natural Science Foundation (Grant No 10574022), and the Funds of the Natural Science of Fujian Province, China (Grant No Z0512006).
文摘We propose an experimentally feasible scheme for preparing a four-atom cluster state in a thermal cavity. In the scheme, the cavity field is only virtually excited and the photon-number-dependent part in the effective Hamiltonian is cancelled so that the system is insensitive to the cavity decay and the thermal field. At the same time, the scheme can be generalized to prepare n-atom cluster states with the success probability 100%. In addition, using the four-atom cluster state, we also propose a simpler scheme for implementing a remote-controlled not gate (CNOT) without the Bell states measurement.
基金Project supported by the National Natural Science Foundation of China (Grant No 10574022)the Natural Science Foundation of Fujian Province of China (Grant Nos 2007J0002 and 2006J0230)the Foundation for Universities in Fujian Province (Grant No 2007F5041)
文摘This paper proposes a scalable scheme to generate n-atom GHZ states and cluster states by using the basic building block, i.e., a weak coherent optical pulse [α) being reflected successively from a single-atom cavity. In the schemes, coherent state of light is used instead of single photon source, homodyne measurement on coherent light is done kastead of single photon detection, and no need for individually addressing keeps the schemes easy to implement from the experimental point of view. The successful probabilities of our protocols approach unity in the ideal case.
基金The project supported by the Natural Science Foundation of Hunan Province of China under Grant No. 05JJ30005, National Natural Science Foundation of China under Grant No. 10474118, the National Fundamental Research Program of China under Grant No. 2005CB724502, the Science Research Foundation of Educational Department of Hunan Province under Grant No. 05C756, and the Science Research Fund of Hunan Institute of Humanity and Science and Technology under Grant No. 2005A008
文摘我们为认识到量纠纷在洞证完在原子之间交换建议一个计划。与洞的仅仅虚拟的刺激在在原子和洞之间的相互作用期间,计划对洞模式状态和洞腐烂感觉迟钝。Theideas 能也为认识到纠纷处于 W 状态处于钟状态和原子层次处于钟状态并且在原子层次之间在一个单个原子和原子层次在原子层次之间交换被利用。
基金Project supported by the National Natural Science Foundation of China (Grant No 10774088)the Key Program of National Natural Science Foundation of China (Grant No 10534030)the Funds from Qufu Normal University, China (Grant No XJ0621)
文摘We propose the methods of generating multipartite entanglement by considering the interaction of a system of N two-level atoms in M cavities of high quality factor with a strong classical driving field. It is shown that, with the cavity detuning, the applied driving field detuning and vacuum Rabi coupling, we can produce an entangled coherent state in two single-mode cavities and generate the entangled coherent cluster states in two bimodal vacuum cavities. Tuning these parameters also allows us to acquire the anti-Jaynes-Cummings (AJC) interaction, with which we can generate the maximally two-photon entangled states, and the two-atom and the two-photon entangled cluster states.
文摘We outline a scheme for entanglement swapping based on cavity QED as well as quasi-Bell state measurement(quasiBSM) methods. The atom–field interaction in the cavity QED method is performed in small and large detuning regimes.We assume two atoms are initially entangled together and, distinctly two cavities are prepared in an entangled coherent–coherent state. In this scheme, we want to transform entanglement to the atom-field system. It is observed that, the fidelities of the swapped entangled state in the quasi-BSM method can be compatible with those obtained in the small and large detuning regimes in the cavity QED method(the condition of this compatibility will be discussed). In addition, in the large detuning regime, the swapped entangled state is obtained by detecting and quasi-BSM approaches. In the continuation,by making use of the atom–field entangled state obtained in both approaches in a large detuning regime, we show that the atomic as well as field states teleportation with complete fidelity can be achieved.
基金Project supported by the International Research & Development Program of the National Research Foundation of Korea(NRF)funded by the Ministry of Education,Science and Technology(MEST)of Korea(Grant No.2011-0030864)the National Natural Science Foundation of China(Grant Nos.11264042and 61068001)+2 种基金the China Postdoctoral Science Foundation(Grant No.2012M520612)the Program for Chun Miao Excellent Talents of Jilin Provincial Department of Education(Grant No.201316)the Talent Program of Yanbian University of China(Grant No.950010001)
文摘A scheme is proposed to generate an N-qubit cluster-type entangled squeezed vacuum state (CTESVS) based on the two-photon interaction between a two-level atomand the cavity fields with the cavity QED system. The CTESVS in N separate cavities can be effectively obtained after performing a simple one-qubit measurement on the atom. The influence of cavity decay on the CTESVS is also discussed.
基金Project supported by the National Natural Science Foundation of China (Grant No 10574022)the Natural Science Foundation of Fujian Province of China (Grant Nos 2007J0002 and 2006J0230)Funds of Education Committee of Fujian Province of China (Grant No JB05334)
文摘This paper proposes schemes for generating multiple-photon and multiple-atom cluster states, respectively. The schemes are based on the cavity input-output process and atomic or photonic states measurement, and the successful probabilities approach unity in the ideal case. The numerical simulations show that the produced multiple-particle cluster states have high fidelity even if the Lamb-Dicke condition is not satisfied. Some practical imperfections, such as atomic spontaneous emission and output coupling inefficiency, only decrease the success probability but exert no influence on the fidelity of generated multiple-particle cluster states. From the experimental point of view, smaller operation number and lack of need for individual addressing keeps the schemes easy to implement. These schemes may offer a promising approach to the generation of a large-scale cluster state.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 60878059, 10947147, 10574022, and 10704010)the Natural Science Foundation of Fujian Province of China (Grant Nos. 2007J0002 and 2010J01002)
文摘Schemes are presented for realizing quantum controlled phase gate and preparing an N-qubit W-like state, which are based on the large-detuned interaction among three-state atoms, dual-mode cavity and a classical pulse. In particular, a class of W states that can be used for perfect teleportation and superdense coding is generated by only one step. Compared with the previous schemes, cavity decay is largely suppressed because the cavity is only virtually excited and always in the vacuum state and the atomic spontaneous emission is strongly restrained due to a large atom-field detuning.
基金supported by the National Natural Science Foundation of China(Grant Nos.61170270 and 61003290)the Specialized Research Fund for the Doctoral Program of Higher Education(Grant Nos. 20091103120014 and 20090005110010)+1 种基金the Beijing Natural Science Foundation(Grant Nos.4122008 and 1102004)the ISN Open Foundation
文摘We present an efficient scheme for undeniable five-party quantum state sharing(FQSTS) of an arbitrary single-atom state with a five-atom cluster state in cavity QED.The implementation of this scheme does not involve the joint-state measurement of multi-atoms,which makes it convenient in a practical application.The scheme is also insensitive to the cavity decay and the thermal field.
基金Supported by the National Natural Science Foundation of China under Grant No.61265001the Natural Science Foundation of Jiangxi Province under Grant No.20122BAB202005+1 种基金the Research Foundation of State Key Laboratory of Advanced Optical Communication Systems and Networks, Shanghai Jiao Tong University under Grant No.2011GZKF031104the Research Foundation of the Education Department of Jiangxi Province
文摘We propose an experimentally feasible protocol for implementing controlled dense coding with a six-atom cluster state in cavity QED. In the scheme, we investigate that the atoms interact simultaneously with the highly detuned single-mode cavity and the strong classical driving field, and thus our scheme is not sensitive to both the cavity decay and the thermal field. In addition, the four-atom entangled states can be exactly distinguished by performing the single-atom measurements in cavity QED, therefore our scheme might be implemented in a simple way.
基金supported by Natural Science Research Project of High Education of Anhui Province (KJ2012Z080)Young Teachers Fund of Anhui University of Science and Technology(2012QNZ13)the Talent Foundation of High Education of Anhui Province for Outstanding Youth(2009QRZ056)
基金This work was supported by the National Science Foundation of China under Grant(No.10574001)the Program of the Education Department of Anhui Province(2004kj029)+1 种基金the Talent Foundation of Anhui Universitythe Youth Program of Fu Yang Normal College under Grant(No.2005LQ03)and(No.2005LQ04)
基金Project supported by the National Natural Science Foundation of China (Grant No 60678022)the Doctoral Fund of the state Education Commission of China (Grant No 20060357008)+2 种基金Anhui Provincial Natural Science Foundation (Grant No 070412060)the Key Program of the Education,Department of Anhui Province (Grant Nos 2006KJ070A and 2006KJ057B)the Talent Foundation of Anhui University,Anhui Key Laboratory of Information Materials and Devices (Anhui University),China
文摘An experimentally realizable physical scheme for preparing multiqubit cluster states from a large detuned atomcavity interaction is proposed. The scheme is free of any type of measurement and insensitive to the cavity decay, and the cavity field is only virtually excited so that there is no information exchanging between atom and cavity. The time required for the gate operations is very short, which is important for decoherence. We also discuss the experimental feasibility of our scheme.
基金Project supported by the Natural Science Foundation of Jiangxi, China (Grant No 0612006) and ECJTU (Grant No 06ZKJC01). We would like to acknowledge useful discussions with Professor Wu Ying.
文摘This paper proposes a scheme where entanglement swapping between atom and cavity can be realized. A-type three-level atoms interacting resonantly with cavity field are considered. By detecting atom and cavity field, it realizes entanglement swapping between atom and cavity. It uses the technique of entanglement swapping to generate an entangled state of two cavity fields by measuring on atoms. It discusses the experimental feasibility of the proposed scheme and application of entangled state of cavity fields.
基金National Natural Science Foundation of China under Grant No.1050402
文摘We propose a scheme to generate atomic cluster states of arbitrary configuration in the cavity quantumelectrodynamics (QED) system.The process is achieved via adiabatic evolution of dark states,which only requiresadiabatically increasing or decreasing Rabi frequencies of laser.Thus it allows the robust implementation of entanglementagainst certain types of errors.Our scheme is relatively decoherence-free in the sense that excited atomic states are neverpopulated and excited cavity photon states can be made negligible in certain conditions.