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Chinese physics B 2013年第7期22卷 420-425页

作者：韩晗 surface physics laboratory (National key laboratory) Key Laboratory of Computational Physical Sciencesand Department of PhysicsFudan University

Under high pressure, the long believed single-phase material CaB6 was latterly discovered to have a new phase tI56. Based on the density-functional theory, the pressure effects on the structural and elastic properties of CaB6 are obtained. The calculated bulk, shear, and Young’s moduli of the recently synthesized high pressure phase tI56-CaB6 are larger than those of the low pressure phase. Moreover, the high pressure phase of CaB6 has ductile behaviors, and its ductility increases with the increase of pressure. On the contrary, the calculated results indicate that the low pressure phase of CaB6 is brittle. The calculated Debye temperature indicates that the thermal conductivity of CaB6 is not very good. Furthermore, based on the Christoffel equation, the slowness surface of the acoustic waves is obtained.

关键词： density-functional theory elastic properties pressure effects acoustic properties

SPUTTERING BEHAVIOUR OF IRON SILICIDES UNDER LOWENERGY Ar^+ ION BOMBARDMENT

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Acta Metallurgica Sinica(English Letters) 1999年第6期12卷 0-0,0-0+0-0页

作者： Z.X. Cao E.G. Wang and YX. Ne(State key laboratory for surface physics, Institute of physics, Beijing 100080, China)

surface compositions of Fe3Si, FeSi and FeSi2 under 0.1 to 5ke V Ar+ bombaniment have been investigated by using AES method, and the results indicate that the sudece compositions depend strongly on ion enerpy and sample bulk compositions. While in FeSi and FeSi2 only Fe enrichment in the selvage has been observed, in Fe3Si it is Si enriched when the ion enerpy is higher than 31OeV Competition between preferential sputtering and radiation enhanced segmpation is quoted to eoplain this phenomenon.

关键词： preferential sputtering iron silicides radiation enhanced segregation

TURNING-OVER OF THE ELECTRIC DIPOLE IN A POLYMER

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Chinese Journal of Polymer Science 2001年第6期19卷 573-578页

作者： Guang-qi Li Xin Sun and Sheng Li State key laboratory of surface physics and Research Center for Theoretical physics, Fudan University Shanghai 200433, China National laboratory of Infrared physics, Shanghai Institute of Technical physics,Shanghai 200083, China Fudan Univ State Key Lab Surface Phys Shanghai 200433 Peoples R China Fudan Univ Res Ctr Theoret Phys Shanghai 200433 Peoples R China Acad Sinica Shanghai Inst Tech Phys Natl Lab Infrared Phys Shanghai 200083 Peoples R China

The transition from the biexciton to the exciton can turn over the direction of the electric dipole of a polymericmolecule. This turning-over action combined with the photoinduced polarization reversion can be used as a switch. Theswitching speed is governed by the relaxation time of the turning-over process, which can be determined by a dynamicalsimulation.

关键词： exciton biexciton electric dipole switch relaxation

Interfacial processes in small molecule organic solar cells

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Science China(physics,Mechanics & Astronomy) 2010年第2期53卷 288-300页

作者： LI WenBin,SONG QunLiang,SUN XiaoYu,WANG MeiLiang,WU HuanRong,DING XunMin & HOU XiaoYuan surface physics laboratory (National key laboratory),Fudan University,Shanghai 200433,China 1. surface physics laboratory (National key laboratory) Fudan University Shanghai 200433 China

This paper presents an overview of the recent progress of small molecule organic solar cells mainly based on the previous worksof our group. We will mainly focus on the interfacial processes in the cells. The dissociation of excitons at electrode/organic andorganic/organic interfaces can be directly observed by transient photovoltage measurements. A simple model including dissociationof excitons at the interface and drift of free carriers in the built-in field is proposed to explain the observed signals of transientphotovoltage. Besides exciton-blocking and preventing damage due to cathode evaporation,blocking permeation of oxygen and/orwater molecules and modulating the built-in field are proposed as functions of the buffer layer between C60 and Al. By the use ofthe inverted structure,a shelf lifetime of over 1500 h is achieved for unencapsulated small-molecule organic solar cells.

关键词： organic solar cell interface organic semiconductor

Peculiar dynamical properties of plutonium hydrides

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Progress in Natural Science:Materials International 2006年第3期16卷 248-254页

作者： MENG Daqiao, ZHU Zhenghe, LUO Deli and JIANG Gang (Institute of Atomic and Molecular physics, Sichuan University, Chengdu 610065, China National key laboratory of surface physics and Chemistry, Mianyang 621907, China) [a]Institute of Atomic and Molecular physics Sichuan University Chengdu China [b]National key laboratory of surface physics and Chemistry Mianyang China

In the present work, the structure and spectra of PuH and PuH2 are defined by B3LYP/SDD method, from which the analytic potential energy function of PuH2 is derived. The analysis of quasi-classical molecular reaction dynamics is performed to study the state-state process of Pu(7Fg) + H2(X1∑g+). It is found that the reaction Pu(7Fg)+H2(X1∑g+)→PuH2(X7B1) has no threshold. The simultaneous hydrogenation process of plutonium with the main product of PuH2 is theoretically proved for the first time.

关键词： hydrogenation reaction of plutonium molecular dynamics density functional theory.

The　Investigation　of　Oxygen　Absorption　over　LaOF　by　Means　of　Raman　Spectroscopy

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Chemical Research in Chinese Universities 1995年第1期11卷 84-86页

作者： ZHOUmXiao-ping CHAO Zi-sheng WANG Shui-juWAN Hui-lin and Tsai Khi-Rui(Department of Chemistry, The National key laboratory ofSolid surface physics Chemistry , Xiamen Uniuarsity, Xianten , 361005 ) XIAMEN UNIV NATL KEY LAB SOLID SURFACE PHYS CHEMDEPT CHEMXIAMEN 361005PEOPLES R CHINA

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关键词： Oxygen species Perturbed oxygen species O_2 absorption

Preparation of InSb nanocrystals embedded in SiO_2 thin films

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Chinese Science Bulletin 1998年第19期43卷 1610-1615页

作者： ZHU Kaigui 1, SHI Jianzhong 1, WEI Yanfeng 2 and ZHANG Lide 1 1. Institute of Solid State physics, Chinese Academy of Science, Hefei 230031, China 2. State key laboratory of surface physics, Fudan University, Shanghai 200433, China Institute of Solid State physics Chinese Academy of Science Hefei China State key laboratory of surface physics Fudan University Shanghai China

InSb nanocrystals embedded in SiO 2 thin films were prepared by rf magnetron cosputtering technique. THe observation by transmission electron microscope showed that InSb nanocrystals dispersed uniformly in SiO-2 matrices. InSb nanocrystals with different sizes can be obtained by changing the annealing condition. The average size of InSb nanocrystals depended on annealing temperature and time, but not on the t 1/3 rules. X-ray photoelectron spectroscopy and X-ray diffraction were also applied to the analyses of the composite thin films.

关键词： InSb nanocrystals radio-frequency sputtering quantum confinement.

Studies on the microstructure,optical and electrical properties of organic microcavity devices based on a porous silicon reflector

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Science China(Technological Sciences) 2005年第2期48卷 191-201页

作者： XIONG Zuhong1, FAN Yongliang2, ZHAN Yiqiang2, ZHANG Songtao2, DING Xunmin2 & HOU Xiaoyuan2 1. School of physics, Southwest China-Normal University, Chongqing 400715, China 2. surface physics laboratory (National key laboratory), Fudan University, Shanghai 200433, China 1. School of physics Southwest China-Normal University 400715 Chongqing China 2. surface physics laboratory (National key laboratory) Fudan University 200433 Shanghai China

A novel type of microcavity organic light-emitting diode based on a porous silicon distributed Bragg reflector (PS-DBR) has first been achieved and its microstructure, optical, and electrical properties have also been investigated in detail. The microcavity is made up of the central active organic multilayer sandwiched between a top silver film and a bottom PS-DBR, formed by electrochemical etching of p++-Si substrate. The field- emission scanning electron microscopy cross-section images show the nanometer-scale layered structure and flat interfaces inside the microcavity. The reflectivity (relative to an Al mirror) of the PS-DBR is up to 99%, and the stopband is about 160 nm wide. Resonant cavity mode appears as a tip in the reflectivity spectrum of the Si-based organic multilayer films, which is a symbol that the Si-based organic multilayer structure is indeed a microcavity. The peak widths of the electroluminescence (EL) spectra from the cavities emitting green and red light are greatly reduced from 85 nm and 70 nm to 8 nm and 12 nm, respectively, as compared with those measured from non-cavity structures. Note that the EL emission from the cavity devices is single-mode, and the off-resonant optical modes are highly suppressed. Moreover, increases of a factor of about 6 and 4 of the resonant peak intensity from the cavities emitting green and red light are also observed, respectively. In addition, the current-brightness-voltage characteristics and effect parameters on the lifetime of the cavity devices are also discussed. The present technique for obtaining enhanced EL emission from Si-based organic microcavity may also be another novel effective method for realizing Si-based optoelectronics device integration.

关键词： electrochemical etching, Si-based microcavity, electroluminescence, organic light-emitting diodes.

Characterization and Tribological Behavior of Octadecene,Dodecene and Undecenoic Acid Films on Si Substrate

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Journal of Materials Science & Technology 2005年第5期21卷 671-674页

作者： Jinfang ZHOU+ and Shengrong YANGState key laboratory of Solid Lubrication, Lanzhou Institute of Chemical physics, Chinese Academy of Sciences, Lanzhou730000, China State key laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

The films of octadecene, dodecene, and undecenoic acid were prepared on H-terminated Si surface in the presence of ultraviolet irradiation. The resulted films were characterized with water-contact angle measurement and infrared spectroscopy. The friction-reducing behavior of the prepared films was examined on a static-dynamic friction coefficient measurement apparatus and on an atomic force microscope. It was found that all the reacted films on the Si substrate showed good friction-reducing ability; especially, the film of the octadecene exhibited the best friction-reducing ability. This was attributed to the transfer of the reacted films onto the counter face with formation of a transfer film on the counterpart surface, which led to the transformation of the sliding between the reacted films and the hard ceramic to fiat between the reacted films and its transfer film on the counterpart surface. The macroscopic and microscopic friction behaviors of the prepared films were dependent on their molecular chain lengths. Thus the octadecene reacted film with the highest degree of ordering arrangement showed the best friction-reducing and antiwear abilities in sliding against Si3N4.

关键词： Alkese Reaction film Hydrogen-terminated silicon Tribological behavior