聚硅氧烷与聚氨酯分子间纠缠对织物风格影响

由于氨基硅油与一般亲水性树脂的复配物在织物表面的干燥过程中存在严重的相分离,难以利用该复配物改善纺织品的亲水性与风格。采用多羟基聚醚、端羟烃基聚硅氧烷、异氟尔酮二异氰酸酯制备非线性有机硅水性聚氨酯,并用于氨基硅油的复配改性。通过SEM、EDS、TG以及DSC对复配物与其整理后的织物进行分析。结果表明,非线性有机硅聚氨酯可以有效与氨基硅油形成分子间纠缠,显著降低两者的微相分离。织物亲水性达到97.9 s,折皱回复角提升到62.0°,表现出新颖的高弹柔软风格特点。

Distribution algorithm of entangled particles for wireless quantum communication mesh networks

With ensured network connectivity in quantum channels, the issue of distributing entangled particles in wireless quantum communication mesh networks can be equivalently regarded as a problem of quantum backbone nodes selection in order to save cost and reduce complexity. A minimum spanning tree（ MST）-based quantum distribution algorithm（ QDMST） is presented to construct the mesh backbone network. First, the articulation points are found,and for each connected block uncovered by the articulation points, the general centers are solved. Then, both articulation points and general centers are classified as backbone nodes and an M ST is formed. The quantum path between every two neighbor nodes on the MST is calculated. The nodes on these paths are also classified as backbone nodes. Simulation results validate the advantages of QDMST in the average backbone nodes number and average quantum channel distance compared to the existing random selection algorithm under multiple network scenarios.

分子振转动量子计算及分子振转动纠缠

随着对于量子计算(机)的深入研究,人们相继提出了不同量子计算的模型.近年来,基于分子振-转激发态的量子计算模型受到了研究者的广泛关注.研究发现,基于分子振动和转动模式的量子计算模型可以很方便地实现多量子比特计算,并且可以获得足够长的退相干时间.同时,分子振转动量子计算的数值模拟也发现各种形式的量子逻辑门均可以获得很高的计算保真度.分子振转动模式之间的纠缠是分子振转动量子计算的一个重要资源,因此,分子振转动纠缠动力学的研究也引起了人们的兴趣.对于分子振转动量子纠缠动力学的研究能够为分子振转动量子计算的进一步研究和应用提供参考.本文对分子振转动量子计算和分子振动纠缠的研究进展做了简要综述.

Partial Teleportation of Entanglement Through Natural Thermal Entanglement in Two-Qubit Heisenberg XXX Chain

Natural thermal entanglement between two qubits with XXX Heisenberg interaction is studied. For the antiferromagnet, increasing coupling strength or decreasing temperature under critical point increases the entanglement. Based on the thermal entanglement as quantum channel, entanglement and information of an input entangled state are transferred via partial teleportation. We find that the entanglement transferred will be lost du~ing the process, and for the entanglement fidelity the partial teleportation is superior to classical communication as concurrence of entangled channel beyond 1/4. We show that both correlation information in input entangled state and individual information of the teleported particle are linearly dissipated. With more entanglement in quantum channel, more entanglement and correlation information can be transferred.

Schemes for Splitting Quantum Information with Four-Particle Genuine Entangled States

We propose two schemes for splitting single- and two-qubit states by using four-particle genuine entangled state as the quantum channel. After the sender performs Bell-basis （or three-partite GHZ- basis） measurements on her particles, and the cooperators operate single-particle measurements on their particles, the state receiver can reconstruct the original state of the sender by applying the appropriate unitary operation. In particular, in the scheme for splitting two-qubit state, the receiver needs to introduce an auxiliary particle and carries out a C-NOT operation.

Deterministic Quantum Key Distribution Using Two Non-orthogonal Entangled States

A deterministic quantum key distribution scheme using two non-orthogonal entangled states is proposed. In the proposed scheme, communicators share key information by exchanging one travelling photon with two random and secret polarization angles. The security of the distributed key is guaranteed by three checking phases in three-way channel and the communicators＇ secret polarization angles.

Multi-mode Coherent-Entangled State Representation and Its Applications

We introduce the so-called coherent-entangled state (CES) in the four-mode Fock space,which makesup a new quantum mechanical representation owing to completeness relation and orthogonal property.Its standardSchmidt decomposition and experimental generation using beam-splitter (BS) are proposed.In addition,its applicationsin quantum optics are presented.Finally,we extend it to multi-mode case and discuss some applications,too.

A Note on Normal Forms of Quantum States and Separability

We study the normal form of multipartite density matrices.It is shown that the correlation matrix(CM)separability criterion can be improved from the normal form we obtained under filtering transformations.Based on CMcriterion the entanglement witness is further constructed in terms of local orthogonal observables for both bipartite andmultipartite systems.

A New Solution to Detectable Byzantine Agreement Problem

We present a new quantum protocol for solving detectable Byzantine agreement problem between threeparties by employing one quantum key distribution protocol.The protocol is suggested by a special four-qubit entangledstate instead of singlet states,which shows that singlet states are not necessary to achieve detectable Byzantine agreement.

Solution to Operator Fredholm Equation in Bipartite Entangled State Representation and Its Applications

Based on the bipartite entangled state representation and using the technique of integration within an ordered product （IWOP） of operators we construct the corresponding operator Fredholm equations and then derive their solutions. As its application we deduce some new bosonic operator identities and new relations about the two-variable Hermite polynomials.

Quantum Distributed Ballot Scheme Based on Greenberger-Horne-Zeilinger State

Motivated by the complementary relations of the Greenberger-Horne-Zeilinger (GHZ) entangled tripletparticlestates,a novel way of realizing quantum distributed ballot scheme is proposed.The ballot information is encodedby local operations performed on the particles of entangled GHZ triplet states,which ensures the security of the presentscheme.In order to guarantee the security of this scheme,the checking phase is designed in detail on the basis of theentangled GHZ triplet state.The analysis shows the security of the proposed scheme.

Dynamic Behavior of Entanglement Between Two Spatially Separated Atoms in Two Dissipative and Driven Cavity Fields

We consider two two-level atoms, interacting with two independent dissipative cavities, each of which is driven by an external source. The two cavity fields are both initially prepared in the coherent states, and the two two-level atoms are initially prepared in the singlet state ｜ψ^-〉 =（｜eg〉 - ｜ge〉 ） / √2. We investigate the influence of the damping constant n, the intensity of the external sources F, and the relative difference of the atomic couplings r on the entanglement between the two atoms. In the dispersive approximation, we find that the entanglement between the two atoms decreases with the time evolution, and the decreasing rate of entanglement depends on the values of F/k, k/ω, and r. For the given small values of F/k and k/ω, on the one hand, the increasing of r favors entanglement decreasing of the atomic system, on the other hand, when r → 1 the entanglement decreasing becomes slower. With the increasing of the value of k/ω, the influence of r on the decreasing rate of entanglement becomes smaller, and gradually disappears for the big value of k/ω.

Quantum Mechanical Correspondence of Poisson Integral Formula

In this paper we set up quantum mechanical correspondence of the Poisson integral formula.We show that Poisson kernel function existing in the transformation between the continuum entangled state representation and its induced state,i.e.the number-difference-correlated amplitude entangled state representation.

Efficient Scheme for Entangling Two Distant Atoms

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.

A New Differential Formula About Product of Polynomials and Its Application in Multi-electron State Physics

We derive a new differential formula about a kind of product of polynomials and then apply it to analyze some properties of multi-electron state ＂related to Laughlin wave function＂. The entangled state representation for describing electrons in uniform magnetic field is used.

Entangling Two Atomic Ensembles Trapped in Separated Cavities

We propose a scheme for the generation of two collections of atoms trapped in distant cavities connected by an optical fiber.The virtual photon exchange leads to the entanglement between these two atomic ensembles.During the operation the atomic system,cavity modes,and fiber are not excited,which is important in view of decoherence.

Optical Operator Method in Two-Mode Case and Entangled Fresnel Operator's Decomposition

Based on the entangled Fresnel operator （EFO） proposed in [Commun. Theor. Phys. 46 （2006） 559], the optical operator method studied by the IWOP technique （Ma et al., Commun. Theor. Phys. 49 （2008） 1295） is extended to the two-mode case, which gives the decomposition of the entangled Fresnel operator, corresponding to the decomposition of ray transfer matrix [A, B, C, D]. The EFO can unify those optical operators in two-mode case. Various decompositions of EFO into the exponential canonical operators are obtained. The entangled state representation is useful in the research.

Voltage-Controlled Quantum Dynamics and Generation Entanglement between Two Separated Quantum-Dot Molecules Embedded in Photonic Crystal Cavities

Voltage-controlled quantum dynamics of two quantum-dot molecules （QDMs） embedded in two separated photonic crystal cavities are theoretically investigated. We show numerically that generation of entangled states and population transfer between the two QDMs can be realized with the same coupling parameters. The effects of parameters deviation and dissipations on generation entangled states be used for realization of new-type of solid state quantum and populations transfer are also discussed. The results may devices and integrated electro-optical devices,

Quantum Network Coding on Networks with Arbitrarily Distributed Hidden Channels

Although perfect quantum network coding has been proved to be achievable, it is stiU puzzling whether it is feasible whenever one or more of the channels are replaced by the hidden ones emerging from quantum entanglement. The question is answered in this paper. First, we propose a quantum network coding protocol over a butterfly network with two hidden channels. Second, we investigate a more generaJ situation, where d-level quantum letters are transmitted through the network containing arbitrarily distributed hidden channels, and prove that quantum network coding on such networks is still achievable.

Dynamical Entanglement of Vibrations in Integrable Dimer and Small Molecules

By means of the reduced-density linear entropy, we investigate the properties of dynamical entanglement of vibrations in integrable dimer and realistic small molecules which are initially in the two-mode squeezed vacuum state. It is found that the entropy of the integrable dimer is periodic for weak coupling strength cl and small squeezing parameter r, and there exists a beat phenomenon for strong el and large r. Moreover, the entropy of the small molecules is quasi-periodic for small r, ＆nd the begt phenomenon occurs in the entropy evolution of the two molecules C2D2 and S02 for large r. Our results might be used for molecular quantum computing based on vibrational states.