排序方式: 共有98条查询结果,搜索用时 15 毫秒
41.
We propose a multi-bit dense coding scheme by using only an Einstein-Podolsky-Rosen(EPR) channel and assistant qubits.It is shown that no matter how many classical bits there are,the quantum channel is always a Bell state.The present dense coding process can also prepare non-local multi-particle Greenberger-Horne-Zeilinger(GHZ) states at one of the participants.The quantum circuits for this dense coding process are constructed,the deterministic implementation method in an optical system based on the cross-Kerr nonlinearities is shown. 相似文献
42.
结合环根论中由具有单位元的单环类所确定的上根就是Brown-McCoy根.本文指出在Γ-环中,鉴于Γ-环单位元的复杂性质使得有幺单Γ-环类确定的上根演变成8个,进而研究了这些根之间及这些根与Γ-环其它根之间的大小关系. 相似文献
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We present a scheme to prepare cluster-type entangled squeezed vacuum states (CTESVS) by considering the two-photon interaction between a two-level atom and a high-quality cavity, driven by a strong classical field. After the realization of simple atomic measurements, the generation of CTESVS in four separate cavities is accomplished within the cavity decay time. In the case of large atom=cavity detuning, the scheme is immune to the effect of atomic spontaneous emission. 相似文献
46.
Time-bin-encoding-based remote states generation of nitrogen-vacancy centers through noisy channels 下载免费PDF全文
We design proposals to generate a remote Greenberger-Horne-Zeilinger(GHZ) state and a W state of nitrogenvacancy(NV) centers coupled to microtoroidal resonators(MTRs) through noisy channels by utilizing time-bin encoding processes and fast-optical-switch-based polarization rotation operations.The polarization and phase noise induced by noisy channels generally affect the time of state generation but not its success probability and fidelity.Besides,the above proposals can be generalized to n-qubit between two or among n remote nodes with success probability unity under ideal conditions.Furthennore,the proposals are robust for regular noise-changeable channels for the n-node case.This method is also useful in other remote quantum information processing tasks through noisy channels. 相似文献
47.
Pairwise thermal entanglement in a three-qubit Heisenberg XX model with a nonuniform magnetic field and Dzyaloshinski-- Moriya interaction 下载免费PDF全文
Pairwise thermal entanglement in a three-qubit Heisenberg XX model is investigated when a nonuniform magnetic field and the Dzyaloshinski-Moriya interaction are included. We find that the nonuniform magnetic field and Dzyaloshinski-Moriya interaction are the more efficient control parameters for the increase of entanglement and critical temperature. For both the nearest neighbour sites and the next nearest neighbour sites, the magnetic field can induce entanglement to a certain extent and the Dzyaloshinski-Moriya interaction can enhance the entanglement to a stable value. The steady value of the nearest neighbour site entanglement C 12 is larger than the next nearest neighbour site entanglement C 13 . An interesting phenomenon is that the entanglement curve of C 12 appears a peak value when the Dzyaloshinski-Moriya interaction is considered in a nonuniform magnetic field. 相似文献
48.
Two schemes of quantum secret sharing are proposed via single electron spin confined in charged QDs inside a single-sided microcavity and a double-sided microcavity, respectively. Both schemes rely on coherent photonspin interaction. The two schemes axe both deterministic and can be extended to multipartite secret sharing. 相似文献
49.
One-step implementing three-qubit phase gate via manipulating rf SQUID qubits in the decoherence-free subspace with respect to cavity decay 下载免费PDF全文
We present a scheme for implementing a three-qubit phase
gate via manipulating rf superconducting quantum interference device
(SQUID) qubits in the decoherence-free subspace with respect to
cavity decay. Through appropriate changes of the coupling constants
between rf SQUIDs and cavity, the scheme can be realized only in one
step. A high fidelity is obtained even in the presence of
decoherence. 相似文献
50.
This paper proposes a scheme to generate arbitrary
four-atom entangled decoherence-free states by using simple linear
optical elements, four one-sided cavities in which four atoms are
confined respectively. By conveniently tuning the titled angle of
one half-wave plate, it can obtain arbitrary four-atom entangled
decoherence-free states with a successful probability of 1 as long as
there is no photon loss. 相似文献