Entanglement COncentration of Entangled Squeezed Vacuum States

By analysing the action of a beamsplitter on squeezed vacuum states(SVSs),it is found that,if the two input light beams of the beamsplitter have the same squeezing amplitude and phase,the output state is a two-mode SVS,If the two input light beams of the beamsplitter have the same squeezing amplitude but a phase difference of π,the output state is a direct porduct state of two single-mode SVS.Based on these results,we propose to distill a maximally entangled SVS from a partially entangled SVS by using a 50/50 beamsplitter and photodetectors.     

远程态制备和远程态测量用核磁共振实验实现

量子隐形传态利用一最大的纠缠通道,经过局域操作和经典通讯(LOCC),将任意一未知量子态从发送者(Alice)传送到远处的接收者(Bob),消耗一个纠缠比特(ebit)和两个经典比特(bit),即1ebit+2cbit*1qubit.     

Entanglement Swapping and Concentration in Multi-Pair Bose-Einstein Condensates

We propose a scheme of entanglement swapping and concentration in a system consisting of multi-pair entangled trapped Bose-Einstein condensates （BECs）. In this scheme, entanglement swapping is accomplished by using interference-pattern joint measurements and detecting the total number of condensed atoms leaking out of relevant traps while entanglement concentration is realized by controlling inter-atomic nonlinear and tunnelling interactions. Three- and four-palr BEC schemes are investigated in detail. It is found that with the increasing number of the entangled pairs, the region of entanglement concentration is broadened and the amount of concentrated entanglement is enhanced.     

过渡金属团簇Me+2(M=Fe、Co、Ni)与CO的化学反应

利用离子阱质谱计和激光溅射技术相结合     

单个原子的二模有效Raman理论研究

研究了单个原子或离子与两束激光量子场相互作用的非线性系统．首先提出描述一次涉及2k（k=1，2，3，…）个光子的光强相关耦合Raman过程的普适模型，然后利用作者发展的一种求解各种非线性Jaynes-Cummings模型的系统方法，精确求解了该普适模型，得到了它的能量本征值和本征矢、演化算符、光子数算符和原子反转算符的解析表达式 关键词：     

李超代数OSP（1,2）的两分量相干态表示

本文构造了李超代数ＯＳＰ（１，２）的一种新的相干态－－两分量相干态。这种两分量相干态形成ＯＳＰ（１，２）代数的一种新表示。获得了ＯＳＰ（１，２）代数的一种非齐次微分实现。分析了这种新相干态的压缩性质。发现ＯＳＰ（１，２）代数的奇生成元可以改变这种两分量相干态的压缩性质。     

Quantum Dense Coding in Multiparticle Entangled States via Local Measurements

We study quantum dense coding between two arbitrarily fixed particles in a (N 2)-particle maxlmally-entangled states through introducing an auxiliary qubit and carrying out local measurements. It is shown that the transmitted classical information amount through such an entangled quantum channel is usually less than two classical bits. However, the information amount may reach two classical bits of information, and the classical information capacity is independent of the number of the entangled particles under certain conditions. The results offer deeper insight into quantum dense coding via quantum channels of multi-particle entangled states.     

Quantum Information Transfer from a Double Quantum Dot System to a Cavity Field＊

In this paper, we propose a scheme to realize quantum information transfer from a double quantum dot （DQD） system to a quantized cavity field. The DQD and the cavity field are treated as a two-state charge qubit and a continuous-variable system, respectively. It is shown that quantum information encoded in the two-state DQD system can be transferred to quantum states of the cavity field with a continuous-variable basis through appropriate projective measurements with respect to the DQD.     

量子离散Fourier变换在离子阱中的实现方案

在Cirac-Zoller模型的框架下,讨论在离子阱中如何利用幺正操作实施 量子离散Fourier变换的方案。由于量子离散Fourier变换可由两个基本操作组