一维玻色气体的绝热非线性探针

宏观非绝热量子隧穿引起的玻色-爱因斯坦凝聚体的悬浮

Levitation of Bose-Einstein condensates induced by macroscopic non-adiabatic quantum tunneling

本文研究了振荡磁场作用下两组分玻色-爱因斯坦凝聚体在不同垂直位置的动力学行为。这里示出了如何适当地调谐磁场的振荡频率导致系统对抗重力的悬浮。这种现象是具有内部自由度的系统中宏观非绝热隧穿的表现。

用非弹性光散射探索从超流到莫特绝缘体态的关联一维玻色气体

Exploring correlated 1D Bose gases from the superfluid to the Mott-insulator state by inelastic light scattering

本文报道了加载在光晶格中的相互作用一维玻色气体通过超流到莫特绝缘体相变的布拉格光谱。基本激发与非零的动量和相关的一维气体的响应是在线性制度。强关联量子相位的复杂性直接表现在具有新颖特征的光谱中。这项工作为精确表征光晶格中关联原子相的状态铺平了道路。

有限温度下一维光晶格中的玻色凝聚气体

Bose-Condensed Gases in a 1D Optical Lattice at Finite Temperatures

研究了有限温度下一维光晶格中玻色凝聚气体的平衡性质。我们假设一个附加的谐波约束是高度各向异性的，其中在径向方向上的约束比在轴向方向上更紧。我们推导出Gross-Pitaeavkill方程和Bogoliubov方程的准一维模型，并数值求解这些方程，以获得冷凝分数作为温度的函数。

两个初始独立玻色凝聚气体间的干涉效应

Interference effects between two initially independent Bose-condensed gases

当两个初始独立的玻色凝聚气体重叠时，我们用二次量子化方法研究了整个系统的密度期望值。在存在原子间相互作用的情况下，基于密度期望值的精确表达式，发现整个系统的密度期望值中存在一个非零的干扰项。的密度期望值的演变示出了不同的耦合常数。本工作清楚地表明，在两个初始独立的凝聚体之间存在相互作用诱导的相干过程。

低维超冷吸引玻色气体中动力学薛定谔猫的形成

Formation of dynamical Schrödinger cats in low-dimensional ultracold attractive Bose gases

当一维有吸引力的玻色气体云被势垒散射时，动力学薛定谔猫就可以形成。一旦形成，这些物体在时间上是稳定的。通过求解含时多玻色子薛定谔方程，得到了散射原子云动能向内能转化的现象及其机理。的影响进行了讨论。

三维光晶格中玻色-爱因斯坦凝聚体的绝热加载

Adiabatic loading of a Bose-Einstein condensate in a 3D optical lattice

实验研究了玻色-爱因斯坦凝聚体绝热加载到光晶格势中的情况。通过云自由膨胀后观察到的干涉图案可见性的相应降低来检测斜坡期间激发的产生。我们专注于超流制度，在那里我们表明，限制的时间尺度是有关的重新分配原子通过单粒子隧穿在整个晶格。

Weakly interacting Bose gases below the critical temperature

We consider a homogeneous non-ideal Bose gas at nonzero temperature in equilibrium below the critical temperature $T_C$ in the framework of finite temperature field theory. An algorithm is described in which a manageable subset of diagrams can be considered which, coupled with a self--consistent condition related to the minimization of the free energy, can be used to obtain physically reasonable results.

Stability of low-dimensional multicomponent Bose gases

I show that in low dimensions the interactions in dilute Bose mixtures are strongly renormalized, which leads to a considerable change of stability conditions compared to the mean-field results valid in the high-density regime. Estimates are given for the two-component Bose-Hubbard model and for the Rb(87)-K(41) mixture.

Nature of 3D Bose Gases near Resonance

In this paper, we explore the nature of three-dimensional Bose gases at large positive scattering lengths via resummation of dominating processes involving a minimum number of virtual atoms. We focus on the energetics of the nearly fermionized Bose gases beyond the usual dilute limit. We also find that an onset instability sets in at a critical scattering length, beyond which the near-resonance Bose gases become strongly coupled to molecules and lose the metastability. Near the point of instability, the chemical potential reaches a maximum, and the effect of the three-body forces can be estima…

Critical velocity of flowing supersolids of dipolar Bose gases in optical lattices

We study superfluidity of supersolid phases of dipolar Bose gases in two-dimensional optical lattices. We perform linear stability analyses for the corresponding dipolar Bose-Hubbard model in the hardcore boson limit to show that a supersolid can have stable superflow until the flow velocity reaches a certain critical value. The critical velocity for the supersolid is found to be significantly smaller than that for a conventional superfluid phase. We propose that the critical velocity can be used as a signature to identify the superfluidity of the supersolid phase in experiment.

The stability of the low-dimensional mixtures of dilute quantum gases

We study the stability of the dilute Bose-Fermi and Bose-Bose mixtures with repulsive interactions in one and two dimensions in terms of the renormalization group. For the Bose-Fermi mixture, we show that the uniform mixture is stable against de-mixing in the dilute limit. For the Bose-Bose mixture, we give the stability conditions in the dilute limit. As a byproduct, we also calculate the critical temperature for the superfluid phase of the two-dimensional Bose-Fermi mixture in the extremely dilute limit.

零温下玻色气体从3D到1D的转变

Transition from 3D to 1D in Bose Gases at Zero Temperature

本文研究了玻色气体在横向圆柱径向上的强简谐约束引起的降维效应。利用广义Lieb-Liniger理论，基于玻色气体横向宽度的变分处理，分析了从三维玻色-爱因斯坦凝聚体到一维Tonks-Girardeau气体的跃迁.最低压缩波型的声速和频率给出了所涉及的状态的清晰特征。我们还研究了负散射长度的情况，导出了玻色气体（均匀、单孤子、多孤子和坍缩）在环形约束中的相图。

相互作用玻色气体的双粒子binding energy

Two-particle binding energy of interacting Bose gases

分析了考虑周围介质影响的两粒子T矩阵的极点。从这个极点导出了玻色-爱因斯坦凝聚（BEC）的相图，它依赖于温度、密度、散射长度和动量。用这种方法得到了发生超流性的临界动量。作为一个新的观察，两粒子结合能与BEC的发生密切相关。有人认为，这可能会对暗能量问题产生宇宙学上的影响。