共查询到19条相似文献,搜索用时 944 毫秒
1.
CHEN Ai-Xi HUANG Ke-Lin DENG Li 《理论物理通讯》2007,48(4):641-644
In this paper, a scheme is proposed for realization of two-qubit controlled-not gates and teleportation of an entangled state of atom-cavity. In this scheme, applying hyperfine levels of atom, we consider A-type three-level atom interacting resonantly or nonresonantly with cavity field that is prepared in σ- polarized. We consider the experimental feasibility of this scheme and compare our results with other schemes. 相似文献
2.
In this paper, we propose a physical scheme to concentrate non-maximally entangled
atomic pure states by using atomic collision in a far-off-resonant cavity. The most
distinctive advantage of our scheme is that the non-maximally entangled atoms may be
far from or near each other and their degree of entanglement can be maximally
amplified. The photon-number-dependent parts in the effective Hamiltonian are
cancelled with the assistance of a strong classical field, thus the scheme is
insensitive to both the cavity decay and the thermal field. 相似文献
3.
A scheme is proposed for generating entangled W states with four
cavity modes. In this scheme, we send a V-type three-level atom
through two identical two-mode cavities in succession. After the
atom exits from the second cavity, the four cavity modes are
prepared in the W state. On the other hand we can obtain
three-atom W states by sending three V-type three-level atoms
through a two-mode cavity in turn. The present scheme does not
require conditional measurement, and it is easily generalized to
preparing $2n$-mode W states and $n$-atom W states. 相似文献
4.
JIA Chun-Xia PENG Zhao-Hui 《理论物理通讯》2008,50(11):1113-1116
In this paper, we present a peculiar tripartite entangled state that is inequivalent to both the GHZ state and the W state, and then propose to implement efficient quantum information processing such as quantum dense coding and teleportation with this entangled state in cavity QED. In this scheme the atoms interact with a highly detuned cavity field with the assistance of a strong classical driven field. It does not require the transfer of quantum information between the atomic system and the cavity, and then our scheme is insensitive to both the cavity decay and the thermal field. 相似文献
5.
LU Dao-Ming ZHENG Shi-Biao 《理论物理通讯》2008,49(2):351-354
A scheme is presented for the generation of entangled states for two atoms trapped in two distant cavities. In the scheme each atom is resonantly coupled with the respective cavity mode and driven by a strong classical field. The detection of a photon decaying from the cavities and passing through a beam-splitter collapses the atoms to an entangled state. The required atom-field interaction time is very short and thus the decoherence effect is suppressed. Our scheme is within the reach of presently available cavity QED techniques. 相似文献
6.
Teleportation of a two-atom entangled state using a single EPR pair in cavity QED 总被引:1,自引:0,他引:1 下载免费PDF全文
We propose a scheme for teleporting a two-atom entangled state in
cavity quantum electrodynamics (QED). In the scheme, we choose a
single Einstein--Podolsky--Rosen (EPR) pair as the quantum channel which
is shared by the sender and the receiver. By using the atom--cavity-field
interaction and introducing an additional atom, we can teleport
the two-atom entangled state successfully with a probability of 1.0.
Moreover, we show that the scheme is insensitive to cavity decay
and thermal field. 相似文献
7.
A potential scheme is proposed to deterministically generate complete sets of entangled photons in the context of cavity quantum electrodynamics (QED). The scheme includes twice interactions of atoms with cavities, in which the first interaction is made in two-mode optical cavities and the second one exists in a microwave cavity. In the optical cavities the atoms are resonant with the cavity modes, while the detuned interaction of the atoms with a singlemode of the microwave cavity is driven by a classical field. The favorable features of our scheme include : ( 1 ) it is very straightforward in implementation because we carry out the scheme by only sending atoms through the cavities. The requirement for the implementation is very close to the reach of current cavity QED techniques. (2) The com- plete set of the entangled two- or more-photon states can be generated deterministically by our scheme, and the implementation time remains constant with the size of the entangled photon states. (3) Our scheme is more efficient than previous proposals with cavities, and the generated photons may be collected much more efficiently, due to cavities, than previous proposals by spontaneous emission. 相似文献
8.
YANG Zhen-Biao 《理论物理通讯》2007,48(4):649-652
A new scheme is proposed for realizing entanglement swapping in cavity QED. The scheme is based on the resonant interaction of two-mode cavity with ∧-type three-level atom, and it involves only a single measurement. In the scheme, the output state after swapping is exactly the maximally entangled state in principle, thus it is prior to the previous one, in which the output state is just approximate. Calculations indicate that our scheme is less influenced by an error. 相似文献
9.
We propose a simple scheme to not only generate GHZ states and W states of the multiparticle but also form a new category of multiparticle entangled states by letting the A-type three-level atoms simultaneously interacting with a coherent cavity field followed by the selective measurements on the cavity mode. We investigate the influence of the cavity dissipation on the generated entangled state and discuss the experimental feasibility of our scheme. It is shown that the intensity of the coherent cavity field plays an instructive role in contribution to state preparation process while the cavity decay and the detuning between the atoms and cavity mode result in the deterioration of the generated entangled state. 相似文献
10.
Teleportation of two-atom entangled state in resonant cavity quantum electrodynamics 总被引:4,自引:0,他引:4 下载免费PDF全文
An alternative scheme is presented for teleportation of a two-atom
entangled state in cavity quantum electrodynamics (QED). It is based
on the resonant atom--cavity field interaction. In the scheme, only
one cavity is involved, and the number of the atoms needed to be
detected is decreased compared with the previous scheme. Since the
resonant atom--cavity field interaction greatly reduces the
interaction time, the decoherence effect can be effectively
suppressed during the teleportation process. The experimental
feasibility of the scheme is discussed. The scheme can easily be
generalized to the teleportation of N-atom
Greeninger--Horne--Zeilinger (GHZ) entangled states. The number of
atoms needed to be detected does not increase as the number of the
atoms in the GHZ state increases. 相似文献
11.
Following a recent proposal ( Phys. Lett. A 346
(2005) 330) about quantum dense coding using a tripartite
entangled GHZ state and W state, this paper proposes an
experimentally feasible scheme for dense coding in cavity QED by
using another peculiar tripartite entangled state. In the scheme
the atoms interact simultaneously with a highly detuned cavity
mode with the assistance of a classical field, the successful
probability of dense coding scheme with this peculiar tripartite
entangled state equals 1. 相似文献
12.
A scheme for concentrating entanglement in two partially entangled Einstein-Podolsky-Rosen (EPR) pairs using repetitious resonant
interactions of the atoms with a single-mode cavity field is proposed. A maximally entangled EPR pair can be deterministically
extracted with the success probability of 1.0. In the scheme, the two logical states of a qubit are represented by the two
lowest levels of an atom while a higher-energy intermediate level is used to facilitate the realization of the unitary operations,
and all the operations required to realize deterministic entanglement concentration can be implemented in a reasonable amount
of time before decoherence sets in. The scheme might be experimentally realizable with presently available cavity QED techniques
and gives a realistic means to realize entanglement concentration deterministically. 相似文献
13.
本文提出利用V-型三能级原子与双模腔场的双光子大失谐相互作用制备W纠缠态,该方案要求三个三能级原子和一个双模腔场,第一个与腔场作用的原子最初处于激发态,第二个和第三个原子均处于基态,腔场最初处于真空态,合适地选择原子与腔场之间的相互作用时间即可获得三原子W纠缠态.并且此方案可以推广至多原子W纠缠态和多腔场W纠缠态的制备;通过计算共生纠缠度研究系统中态的纠缠演化以及热纠缠现象. 相似文献
14.
张蕾 《原子与分子物理学报》2016,33(6)
本文提出利用 型三能级原子与双模腔场的双光子大失谐相互作用制备W纠缠态,该方案要求三个三能级原子和一个双模腔场,第一个与腔场作用的原子最初处于激发态,第二个和第三个原子均处于基态,腔场最初处于真空态,合适地选择原子与腔场之间的相互作用时间即可获得三原子W纠缠态。并且此方案可以推广至多原子W纠缠态和多腔场W纠缠态的制备;通过计算共生纠缠度研究系统中态的纠缠演化以及热纠缠现象。 相似文献
15.
提出基于腔QED技术的多用户间的多原子W态和GHZ态量子信道的建立方案.在量子网络的空闲时段,各个用户和量子交换机共享EPR对.量子交换机通过原子和腔场的相互作用将两个EPR对制备成W态,再与另一个EPR对进行纠缠交换,经过直接测量后为用户建立三原子W态量子信道;同时讨论了四用户间的W态量子信道的建立方案.量子交换机对三个EPR对进行纠缠交换,将三个原子同时与腔场作用,经过直接测量后为用户建立三原子GHZ态量子信道;并将此方法推广到N个用户间的GHZ态量子信道的建立.
关键词:
腔QED
量子信道
量子交换机
纠缠交换 相似文献
16.
We propose a scheme for generating entangled squeezed vacuum states of electromagnetical fields. The scheme is based on cavity QED. In this scheme, an atom interacts, successively, with a classical field, two quantum cavity fields, and another classical field. By detecting the final states of the atom, the two quantum cavity fields will be projected to an entangled state. 相似文献
17.
In this paper, we present a peculiar
tripartite entangled state that is
inequivalent to both the GHZ state and the W state, and then propose to
implement efficient quantum information processing such as quantum dense
coding and teleportation with this entangled state in cavity QED. In this
scheme the atoms interact with a highly detuned cavity field with the
assistance of a strong classical driven field. It does not require the
transfer of quantum information between the atomic system and the cavity,
and then our scheme is insensitive to both the cavity decay and the thermal field. 相似文献
18.
Scheme for Concentration of Unknown Greeberger-Horne-Zeilinger Entangled States via Cavity Decay 下载免费PDF全文
We present a scheme for entanglement concentration of an unknown atomic non-maximally entangled GHZ state via cavity decay. In the scheme, the atom trapped in a cavity is manipulated by laser field, so the maximally entangled GHZ state can be obtained by performing certain operation, which can be realized by illuminating the atom in a cavity. Our method is robust against spontaneous atomic decay. 相似文献
19.
XUE-PING ZANG MING YANG CHAO-QUN DU MIN WANG SHU-DONG FANG ZHUO-LIANG CAO 《Pramana》2016,86(5):1009-1019
We present two schemes for transforming bipartite non-maximally entangled states into a W state in cavity QED system, by using highly detuned interactions and the resonant interactions between two-level atoms and a single-mode cavity field. A tri-atom W state can be generated by adjusting the interaction times between atoms and the cavity mode. These schemes demonstrate that two bipartite non-maximally entangled states can be merged into a maximally entangled W state. So the scheme can, in some sense, be regarded as an entanglement concentration process. The experimental feasibility of the schemes is also discussed. 相似文献