基于耦合腔-玻色-爱因斯坦凝聚系统的量子效应及其操控

Cavity quantum electrodynamics describes the coherent interaction between matter and an electromagnetic field confined within a resonator structure, and is providing a useful platform for developing concepts in quantum information processing. A strong coupling regime can be reached experimentally in which atoms coherently exchange a photon with a single light-field mode many times before dissipation sets in. This has led to fundamental studies with both microwave and optical resonators. To meet the challenges posed by quantum state engineering and quantum information processing, recent experiments have focused on laser cooling and trapping of atoms inside an optical cavity. Cavity-mediated Bose-Einstein condensate (BEC) system has been widely investigated as a promising platform to explore the exotic many-body phenomena in recent years both in theory and experiment due to the superb controllability of both the confining potential geometry and the interatomic interaction. The strong coupling of a Bose-Einstein condensate to the quantized field of an ultrahigh-finesse optical cavity has been achieved experimentally. This opens a conceptually new regime of cavity QED, in which all atoms occupy a single mode of a matter-wave field and couple identically to the light field, sharing a single excitation. This opens possibilities ranging from quantum communication to a wealth of new phenomena that can be expected in the many-body physics of quantum gases with cavity-mediated interactions. In this project, we study quantum effects and their manipulation in coupled cavity-BEC systems. concretely, we will investigate some typical quantum phenomena such as quantum correlations (including quantum entanglement and quantum discord), quantum spin squeezing and atomic coherent quantum tunneling in cavity-BEC systems. We will develop theoretical schemes to generate and manipulate quantum effects in cavity-BEC systems. We wil show quantum phase transition how to affect quantum effects. We will also study spin-orbit coupling effect, impurity-dopped effect, multi-mode effect of the cavity, dipole effect in cavity-BEC systems to reveal new and exotic quantum phenomena in these systems.

由光学微腔和原子玻色-爱因斯坦凝聚（BEC）结合形成了一个光与物质强耦合的杂化系统-腔BEC系统，这一系统中诸多参数的精确可控性为量子效应的产生和操控提供了一个理想平台，是当前超冷原子物理和量子信息领域的研究前沿。本项目集中针对耦合的腔BEC系统，研究系统的量子关联（量子纠缠和量子协错）﹑自旋压缩和原子相干量子隧穿的产生和操控机理，揭示这些量子效应与量子相变的关系，提出产生和操控这些量子效应的新方法。通过探索耦合腔BEC系统自旋轨道耦合效应﹑量子参杂效应﹑多模效应和偶极效应，揭示新奇量子效应。在量子效应的产生、操控和探测等方面形成若干新理论观点﹑概念和模型，为发展光子-原子量子器件提供新原理。这一项目的开展不仅对研究和发现量子效应﹑探索腔BEC等量子复杂系统的量子力学本质特征具有重要意义，而且对发展高精密测量技术和量子信息处理技术等未来的高新技术具有重要指导作用。

由光学微腔和原子玻色-爱因斯坦凝聚(BEC)结合形成了一个光与物质强耦合的杂化系统-腔BEC系统，这一系统中诸多参数的精确可控性为量子效应的产生和操控提供了一个理想平台，是当前超冷原子物理和量子信息领域的研究前沿。本项目的主要研究内容是耦合的腔BEC系统中的量子效应及其操控。具体研究了耦合的腔BEC系统的量子关联﹑自旋压缩和原子相干量子隧穿的产生和操控机理，揭示这些量子效应与量子相变的关系，提出了产生和操控这些量子效应的新方法。研究了BEC系统量子掺杂效应、量子非马尔科夫效应、偶极效应和量子速度极限时间，揭示了这些新奇量子效应的新物理。提出了一个新的量子狄克模型-掺杂的狄克模型，通过调节杂质比特的布居可降低光学腔与BEC发生狄克量子相变的临界耦合强度，克服了长期以来实现狄克量子相变要求在强耦合区的困难。利用BEC自旋压缩特性提出了一种在噪声环境中提高参数评估精度的新方案，表明参数评估精度可以得到海森堡极限。利用原子之间的偶极相互作用提出了操控杂质原子与BEC库的量子非马尔科夫性的新方案，表明可以实现人工环境从马尔科夫性-非马尔科夫性的调控。这些研究结果不仅对研究和发现量子效应﹑探索腔BEC等量子复杂系统的量子力学本质特征具有重要意义，而且对发展高精密测量技术和量子信息处理技术等未来的高新技术具有重要指导作用。