Field Quantization and Spontaneous Emission in Left-handed Material

Recently, research on left-handed materials （LHMs） has attracted considerable attentions. The LHMs are a kind of man-made metameterials which have negative permittivity and negative permeability. These metameterials have many novel properties such as inverse light pressure, and reverse Doppler effect, which lead to many potential applications of LHMs such as superlenses which, in principle, can achieve arbitrary subwavelength resolution. However, though the properties mentioned above are seen to be classical, the quantum phenomena in LHMs have also attracted attentions such as the modified spontaneous emission of atoms in LHME.     

The Second Law of Thermodynamic in Quantum System

The second law of thermodynamics is one of the most fundamental and for-reaching laws of physics. It teaches us that when a closed system undergoes a thermodynamic process the entropy of the system never decreases; it increases, or at least remains constant. If the entropy increases the thermodynamic process is irreversible, otherwise it is reversible. Only ideal thermal process is reversible. In classical world a great number of facts have proved the second law is true. But in quantum world since the quantum coherence and correlations exist we are not sure the second law is still true, at least in principle. This is because that： 1. on the microscopic level the irreversibility is conflict with the reversibility of all fundamental physical laws ; 2. there are not enough evidences to show it is true in quantum world.     

逐步判别分析在城市噪声区域划分中的应用

噪声是城市环境质量的重要指标之一,它给人们带来的影响日益严重,我国于1982年颁布了《城市区域环境噪声标准》(GB3096—82,以下简称国标),噪声区域划分就是为了贯彻国标要求,将城市中各小区划定为某一个噪声适用区域,以便执行国标规定进行噪声的管理与治理,最大限度地保护居民。国标将城市划分为以下各种适用区域:1.居民文教区,要求声级为50分贝以下;2.一类混合区,指一般商业与居民混合区,要求声级为55分贝以下;3.二类混合区,指一般商业、工业、交通与居民混合区,要求声级为60分贝以下;4.工业区,要求声级为65分贝以下,国     

Ψ(2S)粒子及粲夸克偶素物理实验研究——2001年度国家自然科学奖获奖项目介绍

文章介绍2001年度国家自然科学奖二等奖获奖成果，在北京正负电子对撞机上采集了Ψ（2S）粒子大数据样本，开展了粲偶素物理的广泛研究：完成了6个粲偶素涉及质量，宽度和衰变化支比等大批重要参数的首次测量或高精度测量；通过对Ψ（2S）和J／Ψ强衰变性质的比较研究，观察到一系列反常现象，挑战现有理论图像。该项研究成果对量子色动力学的检验与发展具有重要意义，为我国粲偶素物理实验研究的继续发展并保持先进水平奠定坚实基础。     

当代计量学的现状和发展②——20世纪的度量衡,21世纪的量子计量学

介绍了新中国成立以来我国计量科学技术的发展和新取得的成就，并对21世纪的量子计量学作了展望和阐述。     

Multipartite Entanglement Preparation and Quantum Communication with Atomic Ensembles

We propose an experimentally feasible scheme to generate Greenberger-Horne-Zeilinger type of maximal entanglement among three atomic ensembles, and show one of the applications, controlled secure direct communication. The scheme involves laser manipulation of atomic ensembles, quarter- and half-wave plates, beam splitters, polarizing beam splitters and single-photon detectors, which are within the reach of current experimental technology.     

量子光通信

量子光通信是以量子信息论和量子力学为理论基础的一种全光型通信，是正处于开发之中的现代光通信前沿．本文简明地介绍了量子光通信的基本概念与特征，阐明了在这种通信系统中一个光子可将无限的信息传递给无限个分支终端．量子光通信系统分为三个关键性部分，即亚泊松激光器、量子非破坏测量和光子计数器．本文对它们的工作原理、基本特性等分别作了介绍，指出了它们的现状和发展前景．     

胶球研究现状

本文介绍了有关胶球研究的现状,重点介绍确认胶球的一些定性的判据以及实验上已发现的一些可能的胶球候选者.     

Controlled Bidirectional Quantum Direct Communication by Using a GHZ State

A controlled bidirectional quantum secret direct communication scheme is proposed by using a Greenberger- Horne-Zeilinger （GHZ） state. In the scheme, two users can exchange their secret messages simultaneously with a set of devices under the control of a third party. The security of the scheme is analysed and confirmed.