We propose a scheme for preparing four-particle Greenberger-Horne-Zeilinger states using two identical bimodal cavities, each supports two modes with different frequencies. This scheme is an alternative to another pub...We propose a scheme for preparing four-particle Greenberger-Horne-Zeilinger states using two identical bimodal cavities, each supports two modes with different frequencies. This scheme is an alternative to another published work [Christopher C Gerry 1996 Phys. Rev. A 53 4591]. Comparisons between them are discussed. The fidelity and the probability of success influenced by cavity decay for the generated states are also considered.展开更多
This paper proposes a simple scheme for generating a three-atom GHZ state via cavity quantum electrodynamics (QED). The task can be achieved through the interaction between two EPR states, which can be prepared easi...This paper proposes a simple scheme for generating a three-atom GHZ state via cavity quantum electrodynamics (QED). The task can be achieved through the interaction between two EPR states, which can be prepared easily with current technology. In this scheme, the cavity field is only virtually excited during the interaction process, and no quantum information transfer between the atoms and the cavity is required. Thus it greatly prolongs the efficient decoherent time. Moreover, this scheme is also applicable for generating an N-atom GHZ state.展开更多
Schrödinger cat states,consisting of superpositions of macroscopically distinct states,provide key resources for a large number of emerging quantum technologies in quantum information processing.Here we propose h...Schrödinger cat states,consisting of superpositions of macroscopically distinct states,provide key resources for a large number of emerging quantum technologies in quantum information processing.Here we propose how to generate and manipulate mechanical and optical Schrödinger cat states with distinguishable superposition components by exploiting the unique properties of cavity optomechanical systems based on Bose-Einstein condensate.Specifically,we show that in comparison with its solid-state counterparts,almost a 3 order of magnitude enhancement in the size of the mechanical Schrödinger cat state could be achieved,characterizing a much smaller overlap between its two superposed coherent-state components.By exploiting this generated cat state,we further show how to engineer the quadrature squeezing of the mechanical mode.Besides,we also provide an efficient method to create multicomponent optical Schrödinger cat states in our proposed scheme.Our work opens up a new way to achieve nonclassical states of massive objects,facilitating the development of fault-tolerant quantum processors and sensors.展开更多
It is shown that strong coupling of Bose–Einstein condensates to an optical cavity can be realized experimentally. With an additional driven microwave field, we show that a highly nonlinear coupling among atoms in a ...It is shown that strong coupling of Bose–Einstein condensates to an optical cavity can be realized experimentally. With an additional driven microwave field, we show that a highly nonlinear coupling among atoms in a Bose–Einstein condensate can be induced with the assistance of the cavity mode. With such interaction, we can investigate the generation of many body entangled states. In particularly, we show that multipartite entangled GHZ states can be obtained in such architecture with current available techniques.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
We propose two schemes for concentrating unknown nonmaximally tripartite GHZ entangled states via cavity quantum electrodynamics (QED) techniques. The finial pure states obtained from the two schemes are shared by t...We propose two schemes for concentrating unknown nonmaximally tripartite GHZ entangled states via cavity quantum electrodynamics (QED) techniques. The finial pure states obtained from the two schemes are shared by two or three parties. Our schemes only require large-detuned interaction between two driven atoms and the quantized cavity mode, which is insensitive to both the cavity decay and thermal field, thus the schemes are well within current experimental technology.展开更多
<Abstract>We propose two physical schemes,which can teleport unknown atomic entangled states from user A (Alice) to user B (Bob) via GHZ class states as quantum channel.The two schemes are both based on cavity Q...<Abstract>We propose two physical schemes,which can teleport unknown atomic entangled states from user A (Alice) to user B (Bob) via GHZ class states as quantum channel.The two schemes are both based on cavity QED techniques. In the two schemes,teleportation and distillation procedures can be realized simultaneously.The second teleportation scheme is more advantageous than the first one.展开更多
We propose a controlled scheme for teleportation of an arbitrary one or two atomic state via a driven QEDcavity.The scheme does not involve the joint Bell-state-measurement BSM and the probability of successful telepo...We propose a controlled scheme for teleportation of an arbitrary one or two atomic state via a driven QEDcavity.The scheme does not involve the joint Bell-state-measurement BSM and the probability of successful teleportationis 1.We show that the original atomic state cannot be perfectly restored by the receiver without all the agents collaborateand classical communication.展开更多
A model has been established for the interaction between a single-mode optical field and a 2-energy-level cold atom with exact analytic solutions given. The processes of momentum and energy exchanges between the optic...A model has been established for the interaction between a single-mode optical field and a 2-energy-level cold atom with exact analytic solutions given. The processes of momentum and energy exchanges between the optical field and the cold atom due to the interaction between them are discussed in detail, and a formula has been given for the variation of momentum and energy exchange volumes with time t in dress state while both the effects of photon recoil and Doppler effect are taken into consideration.展开更多
We present two schemes for realizing the remote preparation of a Greenberger-Horne-Zeilinger (GHZ) state. The first scheme is to remotely prepare a general N-particle GHZ state with two steps. One is to prepare a qu...We present two schemes for realizing the remote preparation of a Greenberger-Horne-Zeilinger (GHZ) state. The first scheme is to remotely prepare a general N-particle GHZ state with two steps. One is to prepare a qubit state by using finite classical bits from sender to receiver via a two-particle entangled state, and the other is that the receiver introduces N - 1 additional particles and performs N - 1 controlled-not (C-Not) operations. The second scheme is to remotely prepare an N-atom GHZ state via a two-atom entangled state in cavity quantum electrodynamics (QED). The two schemes require only a two-particle entangled state used as a quantum channel, so we reduce the requirement for entanglement.展开更多
基金Project supported by the National Natural Science Foundation of China (Grant Nos 10225421 and 10674025), and the Natural Science Foundation of Fujian Province, China (Grant No 2006J0235).
文摘We propose a scheme for preparing four-particle Greenberger-Horne-Zeilinger states using two identical bimodal cavities, each supports two modes with different frequencies. This scheme is an alternative to another published work [Christopher C Gerry 1996 Phys. Rev. A 53 4591]. Comparisons between them are discussed. The fidelity and the probability of success influenced by cavity decay for the generated states are also considered.
基金Project supported by the National Natural Science Foundation of China (Grant No 10574001) and the Program of the Education Department of Anhui Province (Grant No 2004kj029).
文摘This paper proposes a simple scheme for generating a three-atom GHZ state via cavity quantum electrodynamics (QED). The task can be achieved through the interaction between two EPR states, which can be prepared easily with current technology. In this scheme, the cavity field is only virtually excited during the interaction process, and no quantum information transfer between the atoms and the cavity is required. Thus it greatly prolongs the efficient decoherent time. Moreover, this scheme is also applicable for generating an N-atom GHZ state.
基金supported by the National Natural Science Foundation of China(NSFC)(11935006 and 11774086)the Science and Technology Innovation Program of Hunan Province(2020RC4047)+6 种基金L.-M.K.was supported by the NSFC(1217050862,11935006 and 11775075)X.-W.X.was supported by the NSFC(12064010)Natural Science Foundation of Hunan Province of China(2021JJ20036)Y.-F.J.was supported by the NSFC(12147156)the China Postdoctoral Science Foundation(2021M701176)the Science and Technology Innovation Program of Hunan Province(2021RC2078)B.J.L.was supported by Postgraduate Scientific Research Innovation Project of Hunan Province(CX20210471).
文摘Schrödinger cat states,consisting of superpositions of macroscopically distinct states,provide key resources for a large number of emerging quantum technologies in quantum information processing.Here we propose how to generate and manipulate mechanical and optical Schrödinger cat states with distinguishable superposition components by exploiting the unique properties of cavity optomechanical systems based on Bose-Einstein condensate.Specifically,we show that in comparison with its solid-state counterparts,almost a 3 order of magnitude enhancement in the size of the mechanical Schrödinger cat state could be achieved,characterizing a much smaller overlap between its two superposed coherent-state components.By exploiting this generated cat state,we further show how to engineer the quadrature squeezing of the mechanical mode.Besides,we also provide an efficient method to create multicomponent optical Schrödinger cat states in our proposed scheme.Our work opens up a new way to achieve nonclassical states of massive objects,facilitating the development of fault-tolerant quantum processors and sensors.
基金Supported by the National Fundamental Research Program of China under Grant No.2013CB921804the Program for Changjiang Scholars and Innovative Research Team in University under Grant No.IRT1243the Natural Science Foundation of Anhui Province under Grant No.1408085MA20
文摘It is shown that strong coupling of Bose–Einstein condensates to an optical cavity can be realized experimentally. With an additional driven microwave field, we show that a highly nonlinear coupling among atoms in a Bose–Einstein condensate can be induced with the assistance of the cavity mode. With such interaction, we can investigate the generation of many body entangled states. In particularly, we show that multipartite entangled GHZ states can be obtained in such architecture with current available techniques.
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Project supported by the Natural Science Foundation of the Education Department of Anhui Province, China (Grant Nos 2004kj005zd and 2005kj235) and Anhui Provincial Natural Science Foundation, China (Grant No 03042401) and the Talent Foundation of Anhui University, China.
文摘We propose two schemes for concentrating unknown nonmaximally tripartite GHZ entangled states via cavity quantum electrodynamics (QED) techniques. The finial pure states obtained from the two schemes are shared by two or three parties. Our schemes only require large-detuned interaction between two driven atoms and the quantized cavity mode, which is insensitive to both the cavity decay and thermal field, thus the schemes are well within current experimental technology.
文摘<Abstract>We propose two physical schemes,which can teleport unknown atomic entangled states from user A (Alice) to user B (Bob) via GHZ class states as quantum channel.The two schemes are both based on cavity QED techniques. In the two schemes,teleportation and distillation procedures can be realized simultaneously.The second teleportation scheme is more advantageous than the first one.
基金The project supported by National Natural Science Foundation of China under Grant Nos.60472017 and 10575017
文摘We propose a controlled scheme for teleportation of an arbitrary one or two atomic state via a driven QEDcavity.The scheme does not involve the joint Bell-state-measurement BSM and the probability of successful teleportationis 1.We show that the original atomic state cannot be perfectly restored by the receiver without all the agents collaborateand classical communication.
文摘A model has been established for the interaction between a single-mode optical field and a 2-energy-level cold atom with exact analytic solutions given. The processes of momentum and energy exchanges between the optical field and the cold atom due to the interaction between them are discussed in detail, and a formula has been given for the variation of momentum and energy exchange volumes with time t in dress state while both the effects of photon recoil and Doppler effect are taken into consideration.
文摘We present two schemes for realizing the remote preparation of a Greenberger-Horne-Zeilinger (GHZ) state. The first scheme is to remotely prepare a general N-particle GHZ state with two steps. One is to prepare a qubit state by using finite classical bits from sender to receiver via a two-particle entangled state, and the other is that the receiver introduces N - 1 additional particles and performs N - 1 controlled-not (C-Not) operations. The second scheme is to remotely prepare an N-atom GHZ state via a two-atom entangled state in cavity quantum electrodynamics (QED). The two schemes require only a two-particle entangled state used as a quantum channel, so we reduce the requirement for entanglement.
基金Supported by National Natural Science Foundation of China under Grant Nos. 60678022 and 10704001the Specialized Research Fund for the Doctoral Program of Higher Education under Grant No. 20060357008+2 种基金Anhui Provincial Natural Science Foundation under Grant No. 070412060the Key Program of the Education Department of Anhui Province under Grant Nos.KJ2008A28ZC,KJ2008B265,KJ2009A048Z, 2010SQRLI53ZD, and 2008JQI183the Talent Foundation of Anhui University and Anhui Key Laboratory of Information Materials and Devices (Anhui University)