量子dissonance和量子相变及其动力学演化的理论研究

Quantum correlations have received great attention in recent years, since they occupy an important place in foundamential physics and quantum information theory. Quantum dissonance is one kind of quantum correlation, that is, the reminder of the whole quantum correlation excluding entanglement. The behavior of quantum dissonance in quantum phase transition and under noisy environment has great significance in illustrating the difference and connection between various quantum correlations. This project is planning to study quantum dissonance in quantum phase transition and its dynamical evolution under noisy environments. It mainly contains three parts: (1) The relation between quantum dissonance and quantum phase transition in one dimentional spin chain system; (2) Dynamical evolution of quantum dissonance of two-qubit system under noisy envionments; (3) Improving the anti-noise capability of dissonance by classical fields. This project provides a new perspective for in-depth understanding quantum correlations, and establishes theoretical foundation for future studies and applications of quantum dissonance.

量子关联在基础物理学和量子信息领域中都有着重要的地位，近些年受到人们广泛的关注。量子dissonance是量子关联的一种，与纠缠一起构成系统的全部量子关联。在量子相变和噪声环境下研究量子dissonance的行为对阐明各种量子关联间的区别与联系有着重要意义。本项目计划研究量子dissonance和量子相变的关系及其在噪声环境下的动力学演化问题。主要包含三方面内容：（1）自旋链系统中量子dissonance和量子相变的关系；（2）噪声环境下两qubit系统量子dissonance的动力学演化；（3）经典场对量子dissonance抗噪声能力的影响。本研究为深入认识各种量子关联提供新的视角，为未来dissonance的研究和应用奠定重要的理论基础。

量子关联在量子基础理论及量子信息与计算科学领域中都占有重要地位，而量子dissonance与纠缠一起构成全部量子关联，是研究量子关联的重要组成部分，国内外对这一方面的研究很重视。我们针对量子dissonance方面进行了几个方面的研究。首先，我们研究了量子dissonance在刻画量子相变的应用，即在自旋链系统量子相变点附近量子dissonance的性质，发现量子dissonance在量子相变点附近会出现非常尖锐的突变，比量子纠缠和量子discord能够更加有效的反应量子相变点，是更加敏感的量子相变点指示剂，获得了有意义的研究成果；其次，在噪声环境下，我们研究了量子dissonance的动力学演化情况，分析了量子噪声对量子dissonance的影响，与量子discord的情形进行了比较，发现了比较有趣的现象：在某些初始态下量子discord的变化趋势会发生突然转变，而这个转变点正好也是量子dissonance变化趋势的转变点；最后，我们研究了经典场对噪声环境下原子系统中量子dissonance的影响作用，发现经典场可以起到量子dissonance抗干扰作用。