共查询到20条相似文献,搜索用时 171 毫秒
1.
We present a protocol for multi-party superdense coding
by using multi-atom in cavity quantum electrodynamics (QED).
It is shown that, with a highly detuned
cavity mode and a strong driving field, the protocol is insensitive
to both cavity decay and thermal field. It is even certain to
identify GHZ states via detecting the atomic states. Therefore we can
realize the quantum dense coding in a simple way in the multiparty
system. 相似文献
2.
Niu Xu-Feng Ma Wen-Ping Chen Bu-Qing Liu Ge Wang Qi-Zheng 《International Journal of Theoretical Physics》2020,59(4):1121-1128
International Journal of Theoretical Physics - In this paper, we show a new quantum proxy blind signature scheme based on single particle superdense coding. We only need perform unitary operator on... 相似文献
3.
We propose a quantum superdense coding secure communication scheme
by using GHZ state. This scheme combines the ideas of quantum
superdense coding and sequence transmission. Its distinct
advantage is high source capacity. In addition, in checking eavesdropping, we
need not to destroy quantum entanglement. 相似文献
4.
5.
A physical scheme for the implementation of quantum superdense coding has been proposed in Cavity QED. The detuned interaction
between Λ-type three-level atoms and coherent fields constitute the main superdense coding process. The quantum superdense
coding can be realized in an easier way, and the atoms are not excited during the whole process, so the effect of atomic decay
is eliminated naturally. 相似文献
6.
We consider a stochastic differential equation with a quadratic nonlinearity in the noise. We derive equations for the steady state probability density and joint probability distribution valid beyond a markovian approximation. We do not assume that the strength of the random term is small. The equations are derived for the case of an Ornstein-Uhlenbeck noise and also for a dichotomic noise. A comparison is made. We discuss some examples for which correlation functions and the associated relaxation times are calculated. 相似文献
7.
We present a scheme for quantum superdense coding with hyperentanglement,in which the sender can transfer four bits of classical information by sending only one photon.The important device in the scheme is the hyperentangled Bell-state analyzer in both polarization and frequency degrees of freedom,which is also constructed in the paper by using a quantum nondemolition detector assisted by cross-Kerr nonlinearity.Our scheme can transfer more information with less resources than the existing schemes and is nearly deterministic and nondestructive. 相似文献
8.
The generation of Entangled Qudits and their Application in Probabilistic Superdense Coding 下载免费PDF全文
A scheme of the generation of entangled qutrits is presented, and then is generalized to entangled ququads and entangled qudits. With the entangled qutrits, an experimental scheme of probability superdense coding with only linear optical elements is proposed. It is shown that this scheme will be suitable for the entangled ququads, even for the entangled qudits if some nonlinearity is used. This scheme is feasible in the laboratory with the current experimental technology. 相似文献
9.
We introduce three new quantum protocols involving noisy quantum channels and entangled states, and relate them operationally and conceptually with four well-known old protocols. Two of the new protocols (the mother and father) can generate the other five "child" protocols by direct application of teleportation and superdense coding, and can be derived in turn by making the old protocols "coherent." This gives very simple proofs for two famous old protocols (the hashing inequality and quantum channel capacity) and provides the basis for optimal trade-off curves in several quantum information processing tasks. 相似文献
10.
A helicity entangled tripartite state is considered in which the degree of entanglement is preserved in non-inertial frames. It is shown that Quantum Entanglement remains observer independent. As another measure of quantum correlation, Quantum Discord has been investigated. It is explicitly shown that acceleration has no effect on the degree of quantum correlation for the bipartite and tripartite helicity entangled states. Geometric Quantum Discord as a Hilbert–Schmidt distance is computed for helicity entangled states. It is shown that living in non-inertial frames does not make any influence on this distance, either. In addition, the analysis has been extended beyond single mode approximation to show that acceleration does not have any impact on the quantum features in the limit beyond the single mode. As an interesting result, while the density matrix depends on the right and left Unruh modes, the Negativity as a measure of Quantum Entanglement remains constant. Also, Quantum Discord does not change beyond single mode approximation. 相似文献
11.
基于通信双方预先共享d维二粒子最大纠缠态非定域相关性,信息发送方Bob只需要向信息接收者Alice传送一个粒子,就可以传送logd22比特经典信息,为保护信息的安全,方案采用诱骗光子技术,安全性等价于改进后的原始量子密钥分配方案(Bennett-Brassard 1984,BB84).本文讨论了基于高维纯纠缠态超密编码方案.即通过引入一个附加量子比特,信息接收方对手中的纠缠粒子和附加粒子在执行相应的幺正演化,可以获取dαk2logd2+logd2(αk=minαj,j∈0,L,d-1)比特经典信息.通信双方采用诱骗光子技术确保量子信道的安全建立.与其他方案相比,该方案具有通信效率较高、实用性较强的优点. 相似文献
12.
LIN Qing Li Jian Guo Guang-can 《量子光学学报》2006,12(B08):11-11
提出一种多人控制的N粒子GHZ纠缠态的概率传送方案,m粒子GHZ态就可以胜任m个监控者参与的控制工作。接受者Bob在所有参与者的本地操作和有关测量结果的经典信息的协助下进行适当的幺正操作成功实现量子态的异地重建,传送过程中任意一个参与者的缺席都将导致传送的失败。 相似文献
13.
E.G. Thrapsaniotis 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2001,14(1):43-47
In the present paper we consider the case of an electron under the presence of a single mode field in a cavity linearly polarized
in the z-direction. We adopt the dipole approximation and we derive the full propagator of the electron. In the present case we suppose
that the field is in a coherent state. The parameters of the propagator involve Mathieu functions. Finally we extract the
time evolution of an initially Gaussian wavepacket and its probability density. The present theory is applicable to the interaction
of strong fields with atoms.
Received 17 March 2000 and Received in final form 19 December 2000 相似文献
14.
In this work the Hawking-Unruh effect on the quantum entanglement of bosonic field in background of a spherically symmetric black hole of Gauss-Bonnet gravity is investigated beyond the single mode approximation. The entanglement decreases due to Hawking-Unruh effect. However, it has been shown that the dimensions of space time, Gauss-Bonnet term and the parameter β of initial entangled state would be influenced on this degradation. In our investigation, we consider the accelerated observer either near or far from the event horizon and inspect entanglement degradation for them. The mutual information of this bosonic system is also calculated in beyond the single mode approximation and we show that the mutual information will have different behavior when the Hawking temperature increases. 相似文献
15.
We calculate the entanglement assisted capacity of a multimode bosonic channel with loss. As long as the efficiency of the channel is above 50%, the superdense coding effect can be used to transmit more bits than those that can be stored in the message sent down the channel. Bounds for the other capacities of the multimode channel are also provided. 相似文献
16.
V. P. Tsvetkov 《Physics of Particles and Nuclei Letters》2007,4(5):393-396
The equations describing fast-rotating gravitating superdense configurations with the account of relativistic corrections in the first-order post-Newtonian approximation are obtained. 相似文献
17.
S. A. Podoshvedov 《JETP Letters》2005,81(4):195-197
We present a model to realise a probabilistic quantum teleportation of two-particle mode entangled state through the four-photon quantum channel. Four modes of the two-photon mode entangled state are directly transferred to other spatial four modes of the quantum channel with success probability of 50%. The quantum protocol operates in space of photon number states. A Bell state measurement with four beam splitters and four pairs of detectors in the teleportation protocol is accomplished in the fourfold coincidence basis. 相似文献
18.
Harrow A 《Physical review letters》2004,92(9):097902
We define coherent communication in terms of a simple primitive, show it is equivalent to the ability to send a classical message with a unitary or isometric operation, and use it to relate other resources in quantum information theory. Using coherent communication, we are able to generalize superdense coding to prepare arbitrary quantum states instead of only classical messages. We also derive single-letter formulas for the classical and quantum capacities of a bipartite unitary gate assisted by an arbitrary fixed amount of entanglement per use. 相似文献
19.
Hirokazu Takashima Ryotaro Arita Kazuhiko Kuroki Hideo Aoki 《Physica C: Superconductivity and its Applications》2010
While the functional renormalization group is a powerful theoretical method, the static approximation has been usually adopted in which the Matsubara frequency dependence of vertex functions is ignored. We propose a formalism beyond the static approximation with an efficient parameterization in the Matsubara frequency space for the vertex functions to incorporate the self-energy. 相似文献
20.
James F. Lotspeich 《Optics Communications》1976,18(4):567-572
Inclusion of a quartic term with adjustable coefficient in the Taylor expansion approximation to gaussian index profiles of diffused optical waveguides is shown to provide an improved approximation to the true gaussian curve to beyond the e-folding depth. A first-order perturbation to the square-law “harmonic oscillator” solutions is applied to improve the calculations of mode indexes and to illustrate the manner in which the corrected wave functions are extended deeper into the substrate. 相似文献