原子自发辐射相干效应的量子光力学应用

（限3000字符）With the progress of nanoscience and semiconductor techniques, quantum optomechanics exploring the quantum effects of micro- and nano- optomechanical systems are becoming focus of attentions. Quantum optomechanics not only provides new platforms for quantum information processing and quantum nondemolition measurements, but also possibly offers a route to new tests of quantum theory at unprecedented size and mass scales. In this project, we will start off with the relevant results on cavity optomechanical systems to explore new reliable schemes for achieving ground-state cooling and quantum entanglement of micro- and nano-mechanical oscillator by devising an appropriate atom-assisted hybrid cavity optomechanical system and introducing atomic spontaneously generated coherence (SGC). The detailed contents of our research plan are threefold as given follows: (1) after introducing atomic SGC into a hybrid cavity optomechanical system, we consider how to improve and optimize ground-state cooling of micro- and nano-mechanical oscillator. (2) After introducing atomic SGC into a hybrid cavity optomechanical system, we consider how to enhance and manipulate quantum entanglement of micro- and nano-mechanical oscillator. (3) After achieving ground-state cooling and quantum entanglement of micro- and nano-mechanical oscillator in a hybrid cavity optomechanical system involving atomic SGC, we further explore how the nonlinear feedback arising from micro- and nano-mechanical oscillator affects the intracavity field and atomic spectrum.

（限400字）随着纳米科学和半导体工艺的发展，探究微纳尺度光力学系统量子效应的量子光力学研究正成为关注的焦点。它不但为量子信息处理和量子非破坏性测量提供新的操控平台，而且可能提供一种检验前所未有的尺度和质量范围内量子理论的新方式。本项目拟从我们基于腔光力学系统所获得的相关研究成果出发，通过设计恰当的原子辅助混合腔光力学系统并引入原子的自发辐射相干，为解决微纳机械振子的基态冷却和量子纠缠等关键问题提供可靠的新方案。具体研究内容：（1）在混合腔光力学系统中引入原子自发辐射相干后，考虑如何将其用于改进和优化微纳机械振子的基态冷却。（2）在混合腔光力学系统中引入原子自发辐射相干后，考虑如何将其用于增强和操控微纳机械振子的量子纠缠。（3）当引入原子自发辐射相干的混合腔光力学系统中实现了微纳机械振子的基态冷却和量子纠缠时，进一步探究由微纳机械振子提供的非线性反馈对腔场和原子光谱的影响。

随着纳米科学和半导体工艺的发展，探究微纳尺度光力学系统量子效应的量子光力学研究正成为关注的焦点。它不但为量子信息处理和量子非破坏性测量提供新的操控平台，而且可能提供一种检验前所未有的尺度和质量范围内量子理论的新方式。本项目我们首先基于一个简单的光力学系统研究了利用暗模转移相干信号的方案。结果发现腔模转换效率可以达到1。其次，我们基于四能级Tripod型原子辅助的光力学系统研究了腔模、原子相干和力学模的多个稳态解。结果发现由于非线性反馈的增强，我们可以观察到系统存在的多个稳态解，同时也可以观察到利用原子辅助光力系统实现的双电磁感应透明与利用传统的原子光场实现的双电磁感应透明之间的区别。最后，我们基于三能级梯型原子辅助的光力学系统研究了原子自发辐射相干对腔模以及力学模纠缠的影响。结果发现原子自发辐射相干可以增强腔模以及力学模间的纠缠。本项目的研究成果丰富了基于光力系统的量子信息处理和量子非破坏性测量的理论方案，同时为基于光力系统的量子信息处理和量子非破坏性测量的实验提供了可行的新方案。