自旋轨道耦合超冷费米原子气体

We consider spin-orbit coupled ultracold atomic Fermi gases. We investigate new phenomena and new physics resulting from the interplay of Feshbach resonance and spin-orbit coupling. We plan to conduct our research on four parts as follows: First, employing mean-field theory and functional integral method to study all possible quantum phases of the system, the related quantum phase transitions and critical phenomena. Second, by using analytical and numerical methods we study thermodynamical properties of spin-orbit coupled ultracold atomic Fermi gases. We will try to explain all relevant experimental facts, so as to provide solid theoretical backgrounds for future experimental research. Third, based on Bogolibov de-Gennes theory, we study the nonlinear excitations of the system. We will mainly focus on soliton excitation and vortice excitation of spin-orbit coupled ultracold atomic Fermi gases, with the aim of discovering new features and exotic phenomena of its nonlinear excitations. Fourth, to investigate the spin dynamics of spin-orbit coupled atomic Fermi gases, we start from the fundamental principle of quantum mechanics, and derive the dynamical equation by which the spin dynamics is governed. We will develop numerical methods and computer simulating techniques to study spin relaxation process and the evolution of spin magnetization. We will try to discover new physical phenomena and its underlying physical mechanisms, with the purpose of facilating the development of spinelectronics and quantum control research.

我们考虑自旋轨道耦合超冷费米原子气体.主要研究Feshbach共振物理和自旋轨道耦合相互影响所产生的新现象和新物理。拟集中开展以下四个方面的研究工作: 1.通过平均场理论和泛函积分方法研究系统的各种物相、量子相变和临界现象；2.对自旋轨道耦合超冷费米原子系统的热力学性质进行解析和数值方面的深入研究，对有关实验现象进行解释，并为以后的实验工作提供理论依据；3.在Bogoliubov de-Gennes 理论的基础上对系统的非线性激发进行研究，主要探讨自旋轨道耦合超冷费米原子气体的孤子激发和涡旋激发，以期掌握其非线性激发的特点和奇异现象；4.研究自旋轨道耦合超冷费米原子的自旋动力学行为，从量子力学的基本原理出发，推导自旋演化所遵循的动力学方程。发展数值方法和计算机模拟技术研究自旋驰豫过程以及磁化率演化等。发现新的物理现象和物理机制，推动自旋电子学和量子控制研究的发展。

本项目研究了自旋轨道耦合玻色气体的性质，主要研究了四个方面的内容：.（1）具有Rashba自旋轨道耦合玻色气体的基态和元激发 ；（2）有限温度下自旋轨道耦合玻色气体的热力学性质以及二维情况下的BKT相变特性；.（3）两分量玻色原子在具有三维自旋轨道耦合情况下的基态相图和亚稳态；（4）具有Weyl自旋轨道耦合玻色凝聚体中运动杂质的受到的拖曳力。.我们研究表明，自旋轨道耦合对玻色气体的基态相图、凝聚体的耗散、静态结构因子等有着重要的影响，原因在于自旋轨道耦合使低能态的态密度显著增加，从而增强了量子涨落和热涨落。我们发现在二维下，使的通常的BKT温度降为零。研究表明，自旋轨道耦合凝聚体的临界速度和拖曳力存在各向异性，这对于实验上确定凝聚动量的方向具有重要的意义。