单原子量子真空作用操控的近场光力学理论研究

The project studies theoretically the manipulation of the quantum vacuum action of a two-level atom near a dielectric surface on the quantum properties of the optical field and mechanical motion in a near-field optomechanical system. The main aim of the project is to study and discuss the control of the quantum vacuum action on the atomic level and transition frequency and the effect of the quantum vacuum action on the near-field coupling between a single-atom and cavity evanescent field when the distance between the single-atom and the surface of the micro-cavity wall is a nanoscale. Further, the realization of the steady trapping of the atom near the micro-cavity wall is investigated in detail by regulating the population of the excited state of the atom with the driving optical field and therefore controlling the quantum vacuum force from the attraction to repulsion at a special distance. On this basis, a model of single-atom micro-cavity optomechanical system with strong near-field coupling is established. Correspondingly, the project is to investigate the coherent control of single-atom and the vacuum action on the dynamics and the properties of the optical field inside and outside the cavity. The realization of the directed strong coupling between the single-atom motion and the mechanical motion of the cavity mirror and the generation of the quantum entanglement between them will be studied in detail, the effects of the single-atom and the color noise of the system on the ground-state cooling of a mechanical motion mode are analyzed importantly and the squeezing and measure of a mechanical oscillator’s displacement at the quantum level are explored. Finally, the optimal parameters of the various quantum properties in the system will be provided. The project has an important research value for realizing the control of the micro-cavity optomechanical system by a single-atom, the utilization and detection of the quantum vacuum force and the application of the near-field optomechanics in the quantum information process.

本项目拟从理论上研究邻近电介质表面单个两能级原子量子真空作用对近场光力系统中光场和机械运动量子性质的操控。主要讨论当单原子距离微腔壁表面纳米尺度时，量子真空作用对原子能级和跃迁频率的调控以及对原子与腔倏逝场近场耦合的影响。进一步的，利用驱动光场对单原子激发态布居数进行调控，并使其量子真空力在特定距离时从吸引变为排斥，从而研究单原子在微腔壁附近稳定囚禁的实现。在此基础上，构建单原子近场强耦合微腔光力系统。相应的研究单原子及真空作用对近场光力系统动力学及腔内外光场性质的相干控制，以及研究单原子运动与微腔壁机械运动之间直接的强耦合实现及他们之间量子纠缠产生，分析单原子和系统色噪声对机械运动模式基态冷却的影响，探索机械振子位移在量子水平的压缩和测量，并给出系统中各量子特性优化参数。本项目研究对实现微腔光力系统单原子控制、量子真空力利用和探测以及近场光力学在量子信息处理中应用方面具有重要的研究价值。

本项目拟从理论上研究邻近电介质表面单个两能级原子量子真空作用对近场光力系统中光场和机械运动量子性质的操控。主要讨论当单原子距离微腔壁表面纳米尺度时，量子真空作用 对原子能级和跃迁频率的调控以及对原子与腔倏逝场近场耦合的影响。进一步的，研究单原子及真空作用对近场光力系统动力学及腔内外光场性质的相干控制，以及研究单原子运动与微腔壁机械运动之间直接的强耦合实现及他们之间量子纠缠产生，分析单原子和系统色噪声对机械运动模式基态冷却和压缩的影响，并给出系统中各量子特性优化参数。具体研究了（1）量子辐射体系综与邻近机械振子的量子真空作用对光机械系统动力学行为以及系统中机械运动的量子基态冷却的影响，得出了原子真空作用对量子基态冷却的优化控制。（2）通过单个原子的中介作用实现悬臂梁的机械运动与腔场之间的光机耦合，进一步通过机械运动的正向模分裂和混合光力系统的光学响应演示了系统中真空诱导的强耦合。（3）由一个标准的光力腔中的量子发射器和一个移动镜子组成系统中，利用真空又打的辐射系统-镜子耦合增强混合光机系统的稳态纠缠（4）悬浮光力腔系统与高阶激发原子介质耦合时的光响应特性，得出了原子介质的高阶激发、原子系综的大驱动等对混合系统中的光力诱导透明行为的影响。（5）具有悬浮介电纳米球和高阶激发原子系综的光机力系统中的稳态纠缠，发现其可以通过增加原子的激发数和纳米球的半径进行提升。（6）由悬浮石墨烯片和被囚禁在Fabry-Pérot腔中的超冷原子系综构成的混合光力系统中机械振荡器的宏观量子相干性和机械压缩，得出了量子相干转换的优化条件。(7)得出了由无源腔、无损耗增益腔和与机械振荡器耦合的有源腔组成的光学系统的光响应特性及其参数优化控制。(8) 得出在长时间限制下，通过适当选择调制频率和调制幅度，可以显著地降低机械运动稳态声子数，使机械振荡器冷却到基态。（9）得出了包含一个光学腔和两个机械振子的光力系统的腔模和机械模之间的相干转移。