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Extraction of Surface Roughness from the Central δ-peak of Light Scattering Using a Multi-wavelength Ar~+ Laser

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Chinese Journal of Lasers 2000年第3期9卷 22-27页

作者： LIU Deli QI Dongping CHENG Chuanfu (department of physics,{2., jinan 2.0014, china) 山东师范大学山东济南

In this paper, a new light scattering method for measuring t he roughness of random surfaces is proposed. The method is based on the relation between the specularly reflected intensity I s, i.e., the central δ-peak intensity and wave vector component k z. The linear fit of the logarithm graph of the normalized central δ-peak intensity I sr versus k-2.z, whose variation is induced by changing illuminating wavelength, gives the square of the surface roughness w. The roughnesses of 6 silicon backside samples were measured.

关键词： random surface roughness light scattering multi-wavelength

Study on sea water intrusion into palaeochannels on south coastal plain of the Laizhou Bay by the Bohai Sea

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Acta Oceanologica Sinica 2003年第1期22卷 69-74页

作者： Han Mei Geography department, shandong normal university,{2., china Geography department Shandong Normal University Jinan 250014 China

The palaeochannel evolution in the study region is divided into four stages by such methods as 14C dating. Sea water intrusion through palaeochannels has been studied as a focal point. Palaeochannels are the main passageways through which the sea water intrudes at a higher speed, through many means and in a changeable dynamic state.

关键词： Palaeochannel sea water intrusion south coastal plain of Laizhou Bay

An investigation of hadronization mechanism at a Z^0 factory

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Science china(physics,Mechanics & Astronomy) 2010年第11期53卷 1998-2004页

作者： JIN Yi 1,SI ZongGuo 2.XIE QuBing 2.& YAO Tao 2.1 department of physics,{2. of jinan,jinan 2.002.,china 2.School of physics,shandong {2.,jinan 2.0100,china department of physics University of Jinan Jinan China School of physics Shandong University Jinan China

We briefly review the hadronization pictures adopted in the LUND String Fragmentation Model (LSFM),Webber Cluster Fragmentation Model (WCFM) and Quark Combination Model (QCM),*** of hadron multiplicity,baryon to meson ratios and baryon-antibaryon flavor correlations,especially those related to heavy hadrons at a Z 0 factory obtained by LSFM and QCM,are reported.

关键词： Z0 factory hadronization model baryon to meson ratio B correlation

Recurrence spectra of He atoms in strong external fields

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Science china(physics,Mechanics & Astronomy) 2004年第4期47卷 477-484页

作者： LIN Shenglu1, LI Hongyun1, WANG Dehua2. ZHAO Wenli1 & GAO Feng1 1. department of physics,{2., jinan 2.0014, china 2. department of Mathematics and physics, shandong Institute of Architecture and Engineering, jinan 2.0014, china department of physics Shandong Normal University Jinan China department of Mathematics and physics Shandong Institute of Architecture and Engineering Jinan China

By employing a model potential including the electron exchange energy, we extend the semiclassical closed orbit theory to study the multielectron atoms. Using special region-splitting consistent and iterative method, we figure out the closed orbits in the corresponding classical system and calculate the recurrence spectra of triplet helium atoms in parallel electric and magnetic fields at scaled energy ε=?0.03,n≈40,n=0. The core-scattering effects have been taken into account, which lead to more peaks in the spectra. It has also been confirmed by means of the direct comparison between the spectral portrait in such a plot and those of hydrogen case. In order to compare the theoretic results with experiment, we investigate the closed orbits and recurrence spectra of helium atoms for the similar exchange potential but applied only by single electric field at scaled energy ε=?2.7 case. The spectra are in good agreement with the experimental observation. We conclude that our model is correct and it is necessary to consider the exchange effect for determining the photoabsorption spectra of multielectron atoms in strong external fields.

关键词： exchange potential, recurrence spectra, semiclassical closed orbit theory, core-scattering.

The Ambient Gas Effects on Pulsed Laser Ablation of Target

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光电子·激光 1996年第1期7卷 12-15页

作者： Gongtang Wang Xiangtai Wang Baoyuan Mian(department of physics,{2. normal university,jinan 2.0014)Bingzhang Xu Liangmo Mei(department of physics.{2. university,jinan 2.0100) 山东师范大学物理系山东济南山东大学物理系山东济南

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关键词： Al￣+ ion mean projected range laser ablation ambient gas effect.

The optical near-field speckles and their first order statistics on the basis of the integral equations of electromagnetic field

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Science china(physics,Mechanics & Astronomy) 2004年第3期47卷 365-380页

作者： CHENG Chuanfu1, 2. SONG Hongsheng2. LIU Chunxiang2. REN Xiaorong2. ZHANG Ningyu3, TENG Shuyun1 & XU Zhizhan1 1. Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P. O. Box 800-2.1, Shanghai 2.1800, china 2. department of physics,{2., jinan 2.0014, china 3. shandong Institute of Architecture and Engineering, jinan 2.0014, china Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaichina department of physics{2. normal universityjinanchina shandong Institute of Architecture and Engineeringjinan{2.

From Helmholtz equation of the harmonic electromagnetic waves, the integral equations of the light field at the medium boundaries are obtained by use of the Green's theorem and are discretized into linear equation set with the values of the light field and its derivative as the unknowns. On solving the linear equation set, we realize the rigorous computations of the light fields at the boundaries. Then the intensities of the light waves scattered by the random self-affine fractal surfaces in the optical near-field are calculated, and the propagation characteristics, the evolutions of the contrast and the intensity probability density function of the near-field speckles are studied in detail. The near-field speckles are much different from the conventional speckles in the diffraction regions and in the imaging systems. There are obvious local fluctuations in the intensity distributions of the near-field speckles and such fluctuations disappear after propagating a distance of one wavelength from the medium surfaces. For the random surfaces with smaller lateral correlation lengths, the speckle contrasts approach the saturation values and the speckle fields approach Gaussian distribution within the near-field, while for the random surfaces with larger lateral correlation lengths, such evolutions become comparatively slow.

关键词： speckle, near-field optics, first order statistics, Green's function.

Optical waveguides in LiNbO_3 and stoichiometric LiNbO_3 crystals by proton exchange

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Science china(physics,Mechanics & Astronomy) 2008年第10期51卷 1479-1488页

作者： LI ShiLing College of physics and Engineering, Qufu normal {2., Qufu 2.3165, china School of physics and Microelectronics, shandong {2., jinan 2.0100, china College of physics and Engineering Qufu Normal University Qufu China School of physics and Microelectronics Shandong University Jinan China

The formation of optical planar waveguides in LiNbO3 and stoichiometric LiNbO3 crystals by proton exchange was reported. The prism-coupling method was used to characterize the dark-line spectroscopy at the wavelength of 633 and 1539 nm, re-spectively. The mode optical near-field outputs from proton-exchanged LiNbO3 and SLN waveguides at 633 nm were presented. The mode field from stoichiometric LiNbO3 (SLN) waveguide is lighter and more uniform than that from LiNbO3 waveguide, which means the quality of the waveguide in SLN crystal is better than that of the LiNbO3 waveguide. For proton-exchanged LiNbO3 waveguides, the evo-lution of the refractive index profile with annealing was presented. The disorder profiles of Nb atoms in proton-exchanged LiNbO3 waveguides were obtained by Rutherford backscattering/channeling technique. It is shown that the longer the exchange time, the larger the displacement of Nb atoms.

关键词： optical waveguide proton exchange LiNbO3 crystal stoichiometric LiNbO3 crystal

Electronic structure and magnetism of compound Nd_2.e_(17)N_3

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Chinese Science Bulletin 1998年第4期43卷 278-282页

作者： JIANG Tao and LI Hua department of physics, {2. university, jinan 2.0100, china department of physics Shandong University Jinan 250100 China

The electronic structure and magnetism of compound Nd\-2.e 17 N\-3 has been studied with MS_Xα method. It was found that there are negative exchange couplings between Fe(f) and Fe(c) atoms in Nd\-2.e 17 N x compounds. The interstitial N atoms make the unit cell volume of the compounds increase a little, and hence the strength of negative exchange coupling decreases.

关键词： compounds of R\-2.e 17 type Curie temperature electronic density of states exchange splitting atomic magnetic moment.

STRUCTURE AND MAGNETIC PROPERTIES OF Fe/Pd COMPOSITIONALLY MODULATED FILMS

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Acta Metallurgica Sinica(English Letters) 1993年第8期6卷 112-115页

作者： ZHANG Lin LIU Yihua shandong university,{2.,china WANG Hao Dongnan university,Nanjing,china engineer,department of physics,shandong university,{2. 2.0100,china shandong Univ Jinan China

Metal Fe/Pd compositionally modulated films(CMFs) were prepared by vapour depo- sition from two sources onto glass substrate under *** modulation and crystal structures of the films were examined by X-ray *** magnetic properties were determined by vibrating sample *** Pd layers in the Fe/Pd CMFs are of fcc structure,and the Fe layer structure transits from bcc into amorphous,state with decreasing thickness of Fe *** dependence of specific saturation magnetization on thickness of Fe layers has also been discussed.

关键词： compositionally modulated films modulated structure specific saturation magnetization