腔与自组装量子点分子组成的复合系统的量子纠缠网络

The quantum entanglement network have many advantage over the classical network, such as large storage, fast information processing and transmission. The self-assembled quantum dots can be as ideal storage qubits because can be well fabricated and fast controlled by lasers. Much attention has been drawn to the self-assembled quantum dot molecules because that have richer energy structures than single quantum dots and could easily controlled by lasers. Recently, some researchers show that the self-assembled quantum dots can be strongly coupled to photonic cavities, this kind of system can be used as the interface between the flying and storage qubits. For these reasons, we propose this project to study the quantum dot molecule-cavity system, and built the quantum entanglement network with them. The main contents of this project are the follows: research on the dynamic of the system and their application in quantum entanglement network; explore the control of energy level of single self-assembled quantum dot molecule; built the quantum entanglement network with this system via coherent (or squeeze) light interference.

量子纠缠网络应用了量子纠缠所独有的特性，可突破现有经典网络的物理极限，具有更强信息存贮、处理和传输能力。自组装量子点容易集成和扩展，并且具有很强的光控性，所以是很好的储存比特。而自组装量子点分子具有更加丰富的能级结构，近年来也成为研究热点。随着量子点和腔技术的进步，实验上已经实现了腔和自组装量子点的强耦合。基于此我们将开展腔和自组装量子点分子组成的复合系统量子纠缠网络的研究。其主要内容是：研究腔-自组装量子点分子系统中纠缠动力学演化的相关理论问题及其在量子网络中的应用；探索腔中自组装量子点分子中电子各个能级之间的量子操控；构建通过相干光（或压缩光）干涉来实现腔-自组装量子点分子系统的量子纠缠网络的方案。

全量子网络应用了量子物理学所独有的特性，具有更强信息存贮、读取、处理和传输能力。光子有较强的飞行能力，能在光纤和自由空间信道下保持很好的相干性，适合作为量子信息传输的飞行比特。而量子点容易集成和扩展，并且具有较强的可控性，所以是很好的储存比特。本课题研究结合腔和量子点的优势，利用量子点和腔中光子构建用来实现量子计算的量子纠缠网络。. 本项目主要完成了（1）利用光纤连接的腔实现了两个波色-爱因斯坦凝聚体（BEC）的纠缠；（2）提出了利用空穴隧穿效应实现两个垂直耦合量子点之间的相位门；（3）利用压缩相干态在机械振子光腔中实现微弱测量放大。（4）利用非相干场产生自发相干和泵浦的方法在拉曼达型原子气介质中实现弱光的信息存贮和恢复的方法。 为基于腔和量子点量子信息喝分布式量子计算以及量子测量的进一步研究有着积极意义。