量子关联研究综述

由EPR佯谬，薛定谔“猫态”等超越直观的纯量子现象产生的量子纠缠理论从其概念提出以来一直被人们认为既是量子理论最为重要的概念之一，也是在量子通讯中实现“稠密编码”和“隐形传态”的关键。然而，最近研究结果显示，量子纠缠并不能够完全解释量子关联所有特性。人们发现，除了纠缠以外，还存在对量子信息和量子计算具有极其重要意义的其它非经典关联，如量子失协是一个纯量子比特确定性量子计算机具有计算效率的原因。这说明，量子失协完全可以成为量子计算新的一种资源。文章介绍了非经典关联（包括量子纠缠）的基本概念及其度量方法，对量子失协在各类模型中表现出的量子关联特性进行分析和与量子纠缠，经典关联比较，从而体现出在各类量子体系中对量子失协进行研究的意义，同时引导理论和实验研究者去研究量子失协的潜在研究价值。

A Brief Review on Quantum Correlations

Quantum entanglement generated by the far beyond intuitive pure quantum phenomena such as EPR paradox, Schr？dinger’ s Equation has been considered not only as one of the significant notions in quantum theory but also a key of realizing the“Super Dense Coding” and the“Quantum Teleportation” in quantum communication. However, recent researches show that quantum entanglement is less likely to account for all the properties of quantum correlations. Except for the quantum entanglement, researchers find other non-classical correlations like quan-tum discord, which plays a pivotal role in quantum information and quantum computation and that’ s why the pure qubit-decisive quantum computer possesses computational efficiency. With this clarification, quantum discord completely can be a new resource of quantum computation. In this paper, basic notions and measurement methods of non-classical correlations （ including quantum entanglement ） were discussed and the quantum correlation properties of the quantum discord in various models were analyzed and compared with the quantum entanglement. Conducting researches on the non-classical correlations in various quantum systems are not merely meritorious to the quantum theory, in the mean time, may provide some efficient thoughts and motivations for researchers to employ theoretical concepts about quantum correlations for avoiding decoherence and theoretical scenario for the experiments.