Controlling quantum coherence of atom laser by light with strong strength

A new method for controlling the quantum coherence of atom laser by applying input light with strong strength is presented within the framework of quantum dynamical theory. Unlike the case of rotating wave approximation(RWA), we show that the non-classical properties, such as sub-Poisson distribution and quadrature squeezed effect, can appear in the output atom laser beam with time. By choosing suitable initial RF phase, a steady and brighter output of squeezed coherent atom laser is also available.     

An optical scheme for conditional generation of W state and photon-added coherent state

We propose a simple scheme to generate an arbitrary photon-added coherent state of a travelling optical field by combining an array of degenerate parametric amplifiers and corresponding single-photon detectors. Particularly, when the single-photon-added coherent state is observed by developing the novel technique of Zavatta et al （2004 Science 306 660）, we can simultar/eously obtain the generalized N-qubit W state.     

量子超化学中的类双缝干涉：玻色-爱因斯坦凝聚原子-三聚物相干转化

文章作者首次研究了玻色凝聚体中原子与三原子异核分子间的相干转化过程,特别是双通道量子干涉效应的作用,该效应可以看作是量子简并物质波化学中的类双缝干涉.利用相长干涉可以进一步提高分子制备过程的产率,为异核分子的产生和相干调控提供了一个新的技术.此工作发表在2007年第9卷第133002页的Phys.Rev.Lett上.     

动力学压缩真空与原子间偶极-偶极力

利用Milonni源理论方法研究了动力学压缩真空中两原子间偶极-偶极(d-d)相互作用力的性质与真空压缩的关系.结果发现:由于真空压缩的存在,两原子间d-d吸引力将受到削弱.当压缩系数为零时,得到通常文献中所熟知的结果.     

Scheme for entangling atom-photon pairs via an input light in superposition state

We propose a feasible scheme to create macroscopically entangled atom-photon pairs by preparing an input optical superposition state. Several interesting non-classical quantum statistical effects like the atomic squeezed effects are clearly demonstrated. The making and manipulation of entangled atom-photon pairs are useful for, e.g., high-precision interferometry and quantum information science.     

非线性光机械系统中的弱力探测

从理论上研究了包含光学参量放大器的非线性腔光机械系统的弱力探测性能.一方面,发现通过调节光学参量放大器的非线性增益以及输入光场与腔场之间的有效失谐,可以减小压缩正交中约14 dB的量子噪声,从而将弱力探测灵敏度提高2倍以上.另一方面,分析了非线性腔结合零差测量产生的反作用噪声相消现象并且实现量子非破坏测量的方法.     

动力学压缩真空中的Van der Waals力

基于参数动力学过程产生的压缩效应,利用Millonni源理论方法研究了 动力学压缩真空中Van der Waals力的性质及其与真空压缩的关系。所得结果表明：Van der Waals力的性质依赖于真空压缩的程度;在一定的临界条件下,Van der Waals力由通常的 吸引性作用转化为排斥性作用。当压缩系数为零时,所得结果与通常文献完全一致。     

TIME-DEPENDENT LANDAU SYSTEM AND NON-ADIABATIC BERRY PHASE IN TWO DIMENSIONS

By applying the time-independent unitary transformation, the time-dependent Landau system is transformed into a product of a time-independent Landau system's Hamiltonian and a factor only depending on time, which can be solved exactly. Both the invariant operator and the eigenstate are obtained. In the periodical time-dependent case, the non-adiabatic Berry's phase is also presented.     

量子超化学中的类双缝干涉:玻色-爱因斯坦凝聚原子-三聚物相干转化

文章作者首次研究了玻色凝聚体中原子与三原子异核分子间的相干转化过程,特别是双通道量子干涉效应的作用,该效应可以看作是量子简并物质波化学中的类双缝干涉.利用相长干涉可以进一步提高分子制备过程的产率,为异核分子的产生和相干调控提供了一个新的技术.此工作发表在2007年第9卷第133002页的Phys.Rev.Lett 上.