电-声耦合效应对量子点体系中非经典态性质的影响

The electron-phonon interaction is the main difference of solid-state systems from atomic systems. This proposal will devote to the investigations on theoretical schemes for the influence of the electron-phonon coupling on the properties of nonclassical states in quantum-dot systems. Firstly, for a coherently-driven quantum dot coupled with a optical cavity, we will study how the electron-phonon coupling influence the squeezing of the cavity field when single-photon processes are dominant. New schemes for squeezing the cavity field via dissipative processes will be put forward based on the physical analysis and numerical simulation. Furthermore, searching for the condition in which two-photon processes occur almost resonantly but the single-photon processes occur far-off resonantly, we will explore the influence of the electron-phonon coupling on the properties of two-photon laser field and its squeezing. The temperature of phonon reservoir is also considered during this investigation. Secondly, we will research the influence of the electron-phonon coupling on the properties of the transport current and the resonance fluorescence spectrum of two coupled quantum dots interacting with a single or multiple independent phonon bathes. Additionally, for the cases of the nanomechanical resonator(s) coupled with quantum dot(s), we will propose new schemes for the squeezing of the nanomechanical resonator and discuss the influence of the electron-phonon coupling on the squeezing. Our final goal is to make extension to a precise and self-consistent theory about the contribution of the electron-phonon coupling on the nonclassical states, which can give a precise and appropriate explanation to related experimental results.

电-声耦合效应是固态系统与原子系统最主要的区别。本项目旨在研究量子点体系中电-声耦合效应对非经典态性质的影响。对相干场驱动的单量子点与光腔耦合的系统，我们将探讨电-声耦合效应在单光子跃迁条件下如何影响腔场的压缩性质，结合理论分析和数值计算提出通过耗散过程将腔场压缩的新方案；设计满足双光子跃迁且单光子过程远离共振的条件，进一步研究电-声耦合效应对双光子激光场及其压缩性质的影响；考察声子库的温度效应存在时电-声耦合效应对非经典态影响的区别。其次，我们拟研究耦合双量子点与一个或多个独立的声子库相互作用时，电-声耦合效应对量子点输运性质和共振荧光谱的影响。此外，我们将提出量子点与纳米机械振子耦合时振子压缩的新方案并探讨电-声耦合效应对振子压缩的影响。我们还将发展精确自洽的关于电-声耦合效应对非经典态的影响的理论去解释相关的实验结果。

本项目深入研究了固态量子点系统中非经典态的性质，探讨了电子与声子的耦合效应对不同的量子点系统中的非经典态性质的影响。首先针对相干驱动的单量子点体系，提出了利用量子点与声子库的相互作用将与之耦合的腔场进行压缩的方案，讨论了腔场产生压缩效应的物理机制及电-声耦合效应对腔场压缩性质的影响。将此方案进一步拓展以研究耦合双量子点与纳米机械振子的耦合系统，提出了利用电-声耦合效应将纳米机械振子制备到压缩态的方案。当两个相干驱动场同时驱动量子点与光学微腔时，揭示此系统中的光子阻塞现象出现的物理根源，并探讨了中等耦合强度条件下，电-声耦合效应对光子阻塞现象的影响。对于光子晶体中的微腔光力系统，利用声子库与量子点和光学微腔的相互作用，实现双光子跃迁，提出了一种制备具有非经典性质的非线性相干态的方案，探讨获取的非线性相干态在量子信息处理的可能应用。对于三模光力系统，通过选择性非相干阻尼，提出制备机械振子非经典非高斯态的方案。本项目的完成将深化固态量子点系统中电-声耦合效应的研究，促进量子计算、量子信息处理和精密测量技术的发展。