quantumtransportation.ppt

量子通信 Quantum Teleportation 量子通信 量子通信是指利用量子纠缠效应进行信息传递的一种新型的通讯方式，是近二十年发展起来的新型交叉学科，是量子论和信息论相结合的新的研究领域。 Quantum teleportation is a process by which quantum information (e.g. the exact state of an atom or photon) can be transmitted (exactly, in principle) from one location to another, with the help of classical communication and previously shared quantum entanglement between the sending and receiving location. 量子纠缠quantum entanglement Quantum entanglement is a physical phenomenon that occurs when pairs or groups of particles are generated or interact in ways such that the quantum state of each particle cannot be described independently—instead, a quantum state may be given for the system as a whole. In the quantum formalism, the result of a spin measurement on one of the particles is a collapse into a state in which each particle has a definite spin (either up or down) along the axis of measurement. The outcome is taken to be random, with each possibility having a probability of 50%. However, if both spins are measured along the same axis, they are found to be anti-correlated. quantum entanglement The distance and timing of the measurements can be chosen so as to make the interval between the two measurements spacelike, i.e. from any of the two measuring events to the other a message would have to travel faster than light. 然而由于测不准原理，不能准确测量粒子的全部属性，且测量本身就会改变量子的属性，因此量子通信不仅需要量子信道，还需要经典信道；具体过程： 量子通信 量子通信应用 由于测不准原理和量子不可复制原理，量子通信具有传统通信方式所不具备的绝对安全特性。 2006年夏,我国中国科学技术大学教授潘建伟小组、美国洛斯阿拉莫斯国家实验室、欧洲慕尼黑大学—维也纳大学联合研究小组各自独立实现了诱骗态方案，同时实现了超过100公里的诱骗态量子密钥分发实验，由此打开了量子通信走向应用的大门。2008年底，潘建伟的科研团队成功研制了基于诱骗态的光纤量子通信原型系统，在合肥成功组建了世界上首个3节点链状光量子电话网，成为国际上报道的绝对安全的实用化量子通信网络实验研究的两个团队之一（另一小组为欧洲联合实验团队）。2009年9月，潘建伟的科研团队正是在3节点链状光量子电话网的基础上，建成了世界上首个全通型量子通信网络，首次实现了实时语音量子必威体育官网网址通信。这一成果在同类产品中位居国际先进水平，标志着中国在城域量子网络关键技术方面已经达到了产业化要求。 量子通信应用 量子密钥分发：将量子通信原理仅用于用于发送密匙而不用于数据传输。 Quantum Teleportation Quantum Teleportation Quantum Teleportation Quantum Teleportation Quantum Teleportation