可集成量子计算中的非近邻相互作用

我们研究一维自旋1／2链中的非近邻相互作用的影响。和近邻相互作用相比，非近邻的相互作用强度一般会较弱，因而在以前的许多方案中，这种长程的相互作用被忽略了。本文首先估计由被忽略的非近邻相互作用所引起的量子逻辑门的误差。我们得到的结果是，这项误差不仅和非近邻相互作用的强度有关，更依赖于一维自旋链所包含的粒子数，忽略非近邻相互作用有可能会对可集成量子计算造成影响。我们进一步研究如何消除或者压缩这种长程的相互作用所造成的影响。我们提出了一个量子计算方案。在这种方案中，次近邻的相互作用的影响被完全消除，从而我们可以使量子逻辑门的精度得以提高。我们也讨论了这种方案在超导量子计算体系里面的物理实现问题。     

外FO-群

如果群 G 的所有真商群都是 FO-群,但是群 G 本身不是 FO-群,则称 G 为外 FO-群,本文将给出外 FO-群完全的结构描述．     

Realization of the Fredkin Gate by Three transition Pulses in a Nuclear Magnetic Resonance Quantum Information Processor

We have experimentally realized the Fredkin gate with only three transition pulses in a solution of alanine.It appears that no experimental realization of the Fredkin gate with fewer pulses has been reported yet.In addition,the simple structure of our scheme makes it easy to implement in experiments.     

不可逆热电制冷循环的性能优化准则

考虑了热电制冷循环中热阻、热漏和焦耳热等主要不可逆性，引入了特征参量功率消耗比r，借助装置设计参量X表征了内、外不可逆性，利用有限时间热力学建立了制冷功率、制冷系数与特征参量之间的基本优化关系，导出了协调制冷功率与制冷系数的参量r、X以及电流I的优化准则。     

量子力学创始人海森伯生平简介

 2001年12月5日是量子力学创始人之一海森伯诞辰100周年纪念日。这一天在海森伯成长和工作多年的慕尼黑市组织了有多位世界著名物理学家参加的纪念活动。     

特征与可解性

本文研究了具有不可约特征x使得x(1)²=|G:Z(G)|成立的群G的可解性,并证明了:对于这样的群G,当|Irr(G)|≤4时,G是可解群;当4<|Irr(G)|≤6时,在某些条件下,G是有解群.     

Micro-Photoluminescence Investigation of Single Quantum Dot and its Molecule of CdSe/ZnSe

The single and a few coupled quantum dots are important for future quantum information sciences and their investigation is also a big challenge in physics. We investigate here the electronic and exciton states and their interaction with each other via micro photoluminescence. The luminescence for single and a few dots as well as a dot molecule of CdSe/ZnSe are measured with very high resolution, under liquid He temperature and magnetic fields and with different polarization of excitation laser. The observed sharp spectral lines are attributed to the atomlike transitions of exciton, trion, biexciton… in the investigated single QD or QD molecule. Band filling, Zeeman splitting, spin transition and their relaxation are observed and investigated＇from the spectra and compared with those of same material in different dimensions, and compared with the primary calculation as well. In addition, quite a few new phenomena, which can not be understood based on our present model and knowledge, are also observed; and some very interesting problems are left for further investigation.     

Theoretical Research on a Kind of Quantum Left-handed Metamaterial

Recently, research on left-handed materials （LHMs） has attracted considerable attentions. The LHMs are a kind of metameterial which have negative permittivity and negative permeability, which lead to negative refractive index in a frequency range. The LHMs that have been available so far are in the microwave range and are usually composed of classical particles, such as split-ring resonators. Some quantum phenomena such as spontaneous emission of atoms in the LHMs which are considered to be ＇classical background＇ have also been investigated. Many potential applications of LHMs have been proposed, such as superlenses which, in principle, can achieve arbitrary subwavelength resolution.     

具有模糊数的模糊多目标群体决策优选模型与方法

多目标群体决策问题是运筹学的一个重要研究领域，目前已经提出了一些有效的决策方法。但对目标值和权重均为模糊数的模糊多目标群体决策问题却研究不多，本对此类模糊多目标群体决策问题进行了探讨，利用相对正理想方案与相对负理想方案概念定义了相对差异距离，进而建立了模糊多目标群体决策优选模型与方法，并通过战役决心方案的评价说明了该方法是可行、有效的，可作为军事决策与决策支持系统的备选方法。     

V20+离子1s23d-1s2nf的跃迁能和振子强

用全实加关联方法计算了类锂V20+离子1s23d-1s2nf的跃迁能和偶极振子强度.依据量子亏损理论, 确定了1s2nf系列的量子数亏损,用这些作为能量的缓变函数的量子亏损,实现对该Rydberg系列任意高激发态(n≥10)的能量的可靠预言.将这些分立态振子强度与量子亏损理论相结合,得到在电离域附近束缚态间的偶极跃迁振子强度以及束缚态-连续态跃迁的振子强度密度,从而将V20+离子的这一重要光谱特性的理论预言外推到整个能域.