正则变量的量子隐形传态

利用位置和动量、相位和粒子数这两对正则共轭可观察量,研究了两种不同类型的量子隐形传态方案,把连续变量和分离变量的量子隐形传态统一到正则量子隐形传态的框架中.正则共轭可观察量在量子隐形传态中扮演了三重角色:首先,两个对易的正则可观察量,如相位差和粒子数和的共同本征态提供了一个两系统间的量子通道;其次,对另外两系统的一对正则可观察量进行了Bell基测量;最后,由单个系统的正则共轭观察量构成了两个局域的么正变换以恢复这个未知的量子态.     

Teleportation of an unknown two-particle entangled state via an asymmetric three-particle entanglement state

In this article, a protocol for the teleportation of an unknown two-panicle entanglement is proposed. The feature of the present protocol is that we utilize an asymmetric threeparticle entangled state as the quantum channel. The optimal discrimination between two nonorthogonal quantum states is adopted. It is shown that an unknown two-particle entangled state can be probabilistically teleported from the sender to the remote receiver on condition that the co-sender successfully collaborates. The fidelity in this protocol is one. In addition, the probability of the successful teleportation is calculated and all kinds of transformations performed by the sender and the receiver are provided in detail.     

Perfect Quantum Teleportation via Bell States

Quantum mechanics shows superiority than classical mechanics in many aspects and quantum entanglement plays an essential role in information processing and some computational tasks such as quantum teleportation (QT). QT was proposed to transmit the unknown states, in which EPR pairs, the entangled states, can be used as quantum channels. In this paper, we present two simple schemes for teleporting a product state of two arbitrary single-particle and an arbitrary two-particle pure entangled state respectively. Alice and Bob have shared an entangle state. Two Bell states are used as quantum channels. Then after Alice measuring her qubits and informing Bob her measurement results, Bob can perfectly reconstruct the original state by performing corresponding unitary operators on his qubits. It shown that a product state of two arbitrary single-particle and an arbitrary two-particle pure entangled state can be teleported perfectly, i.e. the success probabilities of our schemes are both 1.     

利用Bell态实现量子隐形传态

量子隐形传态不仅在物理学领域对人们认识与揭示自然界的神秘规律具有重要意义，而且可以用量子态作为信息载体，通过量子态的传送完成大容量信息的传输，实现原则上不可破译的量子保密通信。文章从信息论的角度描述了量子比特、量子纠缠态，如何利用量子线路实现Bell态，提出了一种利用Bell态实现隐形传态的简单结构的量子线路，证明该量子线路是可行的，为进一步研究量子密码通信奠定了基础。     

Optical setups for probabilistic bipartite and tripartite entanglement generation and quantum teleportation in optical networks

In this work we present optical setups for a polarization encoded qubit, based only on common linear optical devices, which implement probabilistic bipartite and tripartite entanglement generation, as well probabilistic quantum teleportation. The setups can be implemented with current technology and they permit the realization of several quantum communication protocols.     

利用两个EPR对隐形传送三粒子纠缠态

提出了一个传送三粒子纠缠态的方案.在方案中,选择两个EPR对作为量子通道,并且引入了一个辅助量子位.通过做控制非门操作及合适的幺正操作,成功地以一定几率传送了三粒子纠缠态.