光子

Based on the principle of special relativity, the formula of "Light Pressure" and the equation of movement of the object propelled by photon propulsion under the condition of movimg object are deduced.

利用狭义相对论推导了物体运动情形下的光压公式和光子推进下物体的运动方程，分析了光子推进过程中的能量转换关系。

Our article mainly discussed the preparation of entangled states and the application of entangled states in quantum communication, including practical scheme for remote state preparation of a photon-photon entangled state, generation and concentration of multi-atom entangled states, practical protocol for telecloning quantum states and protocol for multi-party superdense coding by using multi-atom in cavity QED.This article has several objectives.

本文主要研究了量子纠缠态的制备及纠缠态在量子通信中的应用，包括远程制备光子-光子纠缠态，产生和浓缩多原子纠缠态，利用纠缠态进行远程克隆以及通过腔QED实现多组份密集编码的方案。

The results show that the atomic population is time-independent provided that the atoms are in |β11〉 state. For the other three Bell states, there will appear the periodical collapse revival of atomic populationif the initial mean photon number reaches some special values. With the increase of the initial mean photon number, the oscillation frequency of the time-evolution of atomic population increases correspondingly, and the amplitude decreases. The degree of the entanglement of the two-mode entangled coherent field has no

结果表明，当双原子体系的初态为|β11〉时，原子布居均不随时间变化；当双原子体系的初态为|β00〉，|β01〉或|β10〉且初始平均光子数达到一定值时，演化特性呈现周期性的崩塌-回复效应，并随初始光子数的增加，其演化曲线的振荡频率增大，振幅减小；双模纠缠相干光场的纠缠程度不影响Rabi振荡频率，但对振幅影响显著； Kerr介质与光场耦合系数达到一定值时，对Rabi振荡频率和幅度及原子布居的崩塌-回复周期产生强烈影响。

Based on the objective lens and voice coil motor of the current DVD pickup head,according to photobleaching three-dimensional (3D) optical information storage's theory of two-photon absorption,the Ti∶sapphire femtosecond pulse laser was used as written optical beam and reading optical beam of two-photon three-dimensional optical storage voice coil motor was carried through multiplayer choice, and the storage and readout experimental study of binary format code with two-photon photobleaching in the new photobleaching material consisting of stilbene derivant was conducted.

基于现有的DVD光头物镜与音圈电机，根据光致漂白的双光子吸收三维光信息存储原理，以钛蓝宝石飞秒脉冲激光进行双光子光信息写入和读出，利用音圈电机进行选层，在新型光致漂白材料二苯乙烯衍生物中进行光致漂白二进制编码信息的存储和读出实验研究；实现了三层光信息存储，信息点间距和信息层间距分别为4 μm和15 μm；用Matlab软件读出信息的信号强度并对其进行了识别，识别结果与写入的二进制编码信息完全一致。

When photon acts as the medium of electric field, the photon will be polarized and called photonic polaron.

当光子作为电场的介质时，光子表现出极性，称为光极子

However, the polarization and phase states of photons in the fiber will change according to the environmental changes.

然而在光子的传输过程中时，由于外界环境的变化，随机地改变了光子的偏振性和相位特性。

The production and measurement of single photons are also discussed.

简述了单光子的产生与检测技术，讨论了与单光子有关的新实验。

Photonics Science and Technology Research Center,College of Science,Harbin Engineering University,Harbin 150001,China

哈尔滨工程大学理学院光子科学研究中心，哈尔滨 1500013。哈尔滨工程大学理学院光子科学与技术研究中心，哈尔滨 150001

We pointed out again that the inclusion of the intrinsic transverse momentum distribution of partons leads to an enhancement of photon production cross section in the region of photon trans- verse momenta of a few GeV/c.

结果表明考虑部分子内禀横动量分布导致在光子横动量为几个GeV／c区域内光子产生截面的增加。

Two-dimensional photonic crystal possess only pseudo photonic band gaps, so it is interesting and meaningful that whether the spontaneous emission of the atoms in two-dimensional photonic crystals can be controlled effectively.

二维光子晶体只有赝带隙，因此能否利用二维光子晶体有效控制原子自发辐射是令人感兴趣也是有实际意义的问题。

Shop assistant: Please check at the door.

店员：请您到门口柜台交费。

In the end, transportation of PAHs in the environmental matrix was preliminarily investigated and discussed according to PAHs data of soils and sediments from a certain region in Shanghai. The result indicated that there are two or more pathways on PAHs transportation in the environmental matrix.

最后，对上海特定地区内PAHs在环境介质中的迁移径途进行了分析讨论，结果表明上海市土壤和沉积物等环境介质中PAHs的迁移存在多种途径。