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混合磁性薄膜矫顽力及阶梯效应的微磁学及Monte Carlo研究

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物理学报 2004年第9期53卷 3177-3185页

作者：翁臻臻冯倩黄志高都有为福建师范大学物理与光电信息科技学院南京大学固体微结构国家重点实验室南京210093 南京大学固体微结构国家重点实验室

采用能量极小原理的微磁学及MonteCarlo方法对铁磁反铁磁混合磁性薄膜的磁特性进行了模拟计算 ,研究了基态下系统的磁滞回线、自旋组态及铁磁交换作用常数JAA、单轴各向异性常数K、偶极相互作用常数D和铁磁性原子掺杂量X对矫顽力Hc 的... 详细信息

采用能量极小原理的微磁学及MonteCarlo方法对铁磁反铁磁混合磁性薄膜的磁特性进行了模拟计算 ,研究了基态下系统的磁滞回线、自旋组态及铁磁交换作用常数JAA、单轴各向异性常数K、偶极相互作用常数D和铁磁性原子掺杂量X对矫顽力Hc 的影响 .同时还模拟计算了矫顽力Hc 的温度特性 .模拟结果表明 ,在混合磁性薄膜中磁滞回线存在明显的阶梯效应 ,利用简单的Ising模型揭示这种阶梯效应主要起源于包含不同反铁磁原子的掺杂量的不同尺寸的原子团对外加磁场所产生不同响应 ;在基态下当 0 5≤X≤ 1 0时矫顽力Hc 随K ,JAA 的增大而增大 ,但随D增大而减小 ;Hc 随X的变化存在极大值 .这些结果很好地解释了具有反铁磁耦合的颗粒膜的实验事实 .不同X下矫顽力随温度的变化规律可以用Tα 律很好地描述。

关键词：混合磁性薄膜矫顽力阶梯效应微磁学蒙特卡罗分析磁滞回线自旋组态

ZnO nanostructures prepared by thermal evaporation

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ZnO nanostructures prepared by thermal evaporation

GROWTH AND ELECTRICAL PROPERTIES OF LANIO3.PB(ZR0.61TI0.3.)O3.LANIO3.LAALO3.LL-PEROVSKITE

Ⅻ International Symposium on Small Particles and Inorganic Clusters

作者： Jing Wang Di Wu Xiaoning Zhao Yanfeng Chen Aidong Li and Naiben MingNational laboratory of solid state {3. and department of Materials Science andEngineering nanjing university nanjing 210093 china

＜正＞ A variety of ZnO nanostructures, including nanowires, nanorods, nanotetrapods, nanotubes, nanorod-nanoribbon junctions and nanorings, have been achieved by a thermal evaporation process. These nanoentities were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy （TEM）. All these nanoentities were found

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GROWTH AND ELECTRICAL PROPERTIES OF LANIO3/PB(ZR0.61TI0.39)O...

Ⅰ类和Ⅱ类准周期半导体超晶格的电子子带和波函数

第8届国际材联电子材料国际研讨会

作者： Shan-Tao Zhang, Wei-Shi Tan, Xiao-Jun Zhang Guo-Liang Yuan, Yuan Wang, Yan-Feng Chen, Zhi-Guo Liu , Nai-Ben Ming National laboratory of solid state {3. & department of Materials Science and Engineering, nanjing university, nanjing 210093, People’s Republic of china National laboratory of solid state {3. & department of {13., nanjing university, nanjing 210093, People’s Republic of china

Using a pulsed laser deposition technique, rhombohedral Pb(ZrTiO (PZT) thin films were fabricated on (001) LaAlO (LAO) single crystal substrates with LaNiO (LNO) buffer layer. X-ray diffraction (XRD) measurements on LNO/LAO and PZT/LNO/LAO revealed that the LNO and PZT films were highly c-axis oriented, consistent with the atomic force microscopy (AFM) surface morphologies. The Zr:Ti ratio and

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物理学报 1989年第3期38卷 366-375页

作者：秦国毅南京大学固体微结构物理实验室

本文将包迹函数近似推广用于计算有理数近似下,垂直于超晶格轴的波矢K_⊥不等于零时,准周期半导体超晶格(QSS)的电子子带和波函数,对K_⊥=0的情形,分别计算了Ⅰ类的GaAs/Al_xGa_(1-x)As和Ⅱ类的InAs/GaSb QSS的电子子带和波函数,直至代... 详细信息

本文将包迹函数近似推广用于计算有理数近似下,垂直于超晶格轴的波矢K_⊥不等于零时,准周期半导体超晶格(QSS)的电子子带和波函数,对K_⊥=0的情形,分别计算了Ⅰ类的GaAs/Al_xGa_(1-x)As和Ⅱ类的InAs/GaSb QSS的电子子带和波函数,直至代序数m=9和6。对于价带对导带影响强的InAs/GaSb QSS,分别计算了m=5和6时电子子带随K_⊥的变化关系。并提出了利用本文结果计算Ⅰ类的GaAs/Al_xGa_(1-x)As QSS带间集体激发的具体方法。

关键词：半导体超晶格电子子带波涵数

Characterization of ultrathin SiO2/Si interface grown by low temperature plasma oxidation

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Progress in Natural Science:Materials International 2002年第4期 75-78页

作者： MA Zhongyuan, BAO Yun, CHEN Kunji, HUANG Xinfan, WANG Li, JIANG Ming, SHI Jianjun, LI Wei, XU Jun, LIU Jiayu and FENG Duan(state Key laboratory of solid state microstructures and department of physics, nanjing university, nanjing 210093, china) state Key laboratory of solid state microstructures and department of physics Nanjing University Nanjing 210093 China

Ultrathin SiO2 layers on Si (100) wafers were prepared by plasma oxidation at a low temperature (250℃) . The analyses of X-ray photoelectron spectroscopy (XPS) and TEM reveal that the chemical composition of the oxide layer is stoichiometric SiO2 and the SiO2/Si interface is abrupt. The thickness of the ultrathin oxide layer obtained from XPS, capacitance-voltage (C-V) and ellipsometry measurements indicate a nonlinear time dependence. The high frequency C-V characterization of MOS structure shows that the fixed charge density in SiO2film is about 1011 cm-2. It is also shown that the strength of breakdown electrical field of SiO2 film with 6 nm thickness is of the order of 106 Vcm-1 . These properties of the ultrathin SiO2 layer ensure its application in silicon quantum devices.

关键词： plasma oxidation X-ray photoelectron spectrum ultrathin SiO2 film.

MAGNETIC　RELAXATION　AT　EARLY　TIMES　AND　FLUX　DIFFUSION　BARRIER　V（J，B，T）　FOR　Ti－1223.DOPED　WITH　Pb　AND　Ba　BY　COMPLEX　AC　SUSCEPTIBILITY　MEASUREMENTS

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南京大学学报(自然科学) 1995年第2期 185-186页

作者： Ding Shiying Wang Guoqiang Yao Xixian Pen Huotian Pen Qiuyun Zhou Sibal (department of physics and National laboratory of {3. state Microstrnctures, Center for Advance Studies in Science and Technology of microstructures, Naming university, 210093

ＭＡＧＮＥＴＩＣＲＥＬＡＸＡＴＩＯＮＡＴＥＡＲＬＹＴＩＭＥＳＡＮＤＦＬＵＸＤＩＦＦＵＳＩＯＮＢＡＲＲＩＥＲＶ（Ｊ，Ｂ，Ｔ）ＦＯＲＴｉ－１２２３ＤＯＰＥＤＷＩＴＨＰｂＡＮＤＢａＢＹＣＯＭＰＬＥＸＡＣＳＵＳＣＥＰＴＩＢＩ... 详细信息

ＭＡＧＮＥＴＩＣＲＥＬＡＸＡＴＩＯＮＡＴＥＡＲＬＹＴＩＭＥＳＡＮＤＦＬＵＸＤＩＦＦＵＳＩＯＮＢＡＲＲＩＥＲＶ（Ｊ，Ｂ，Ｔ）ＦＯＲＴｉ－１２２３ＤＯＰＥＤＷＩＴＨＰｂＡＮＤＢａＢＹＣＯＭＰＬＥＸＡＣＳＵＳＣＥＰＴＩＢＩＬＩＴＹＭＥＡＳＵＲＥＭＥＮＴＳＤ...

关键词： magnetic Relaxation ac susceptibility Tl1223.superconductor

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团簇物理的新进展（Ⅰ）

物理学进展 1994年第2期14卷 121-172页

作者：王广厚固体微结构物理国家重点实验室南京大学物理系

本文较系统地论述了团簇研究在制备、结构和性质等方面的最新进展，其中包含了本实验室近年来在团簇物理方面所取得的重要成果。并对当前团簇研究存在的问题和发展方向作了展望。

关键词：团簇物理原子团簇分子团簇进展

Grouping of amino acids and recognition of protein structurally conserved regions by reduced alphabets of amino acids

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Science china(Life Sciences) 2007年第3期50卷 392-402页

作者： LI Jing1 & WANG Wei1,2 1 National laboratory of solid state Microstructure and {3. of physics, nanjing university, nanjing 210093, china 2 Interdisciplinary Center of Theoretical Studies, Chinese Academy of Sciences, Beijing 100080, china 1. National laboratory of solid state Microstructure and {3. of physics Nanjing University Nanjing 210093 China 2. Interdisciplinary Center of Theoretical Studies Chinese Academy of Sciences Beijing 100080 China

Sequence alignment is a common method for finding protein structurally conserved/similar regions. However, sequence alignment is often not accurate if sequence identities between to-be-aligned se- quences are less than 3.%. This is because that for these sequences, different residues may play similar structural roles and they are incorrectly aligned during the sequence alignment using substitu- tion matrix consisting of 20 types of residues. Based on the similarity of physicochemical features, residues can be clustered into a few groups. Using such simplified alphabets, the complexity of protein sequences is reduced and at the same time the key information encoded in the sequences remains. As a result, the accuracy of sequence alignment might be improved if the residues are properly clustered. Here, by using a database of aligned protein structures (DAPS), a new clustering method based on the substitution scores is proposed for the grouping of residues, and substitution matrices of residues at different levels of simplification are constructed. The validity of the reduced alphabets is confirmed by relative entropy analysis. The reduced alphabets are applied to recognition of protein structurally conserved/similar regions by sequence alignment. The results indicate that the accuracy or efficiency of sequence alignment can be improved with the optimal reduced alphabet with N around 9.

关键词： Grouping of amino acids and recognition of protein structurally conserved regions by reduced alphabets of amino acids

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内电场对纳米硅光致发光谱的影响

物理学报 2004年第4期53卷 1236-1242页

作者：黄凯王思慧施毅秦国毅张荣郑有炓南京大学物理系固体微结构国家重点实验室南京210093

从量子限制发光中心模型出发 ,计算了纳米硅的光致发光 (PL)特征与发光中心间的关系 .研究发现 ,纳米硅与发光中心间的内电场对载流子复合率及峰位振荡有着十分重要的影响 .在 2— 5nm的尺寸范围内 ,纳米硅发光中心上的载流子复合概率... 详细信息

从量子限制发光中心模型出发 ,计算了纳米硅的光致发光 (PL)特征与发光中心间的关系 .研究发现 ,纳米硅与发光中心间的内电场对载流子复合率及峰位振荡有着十分重要的影响 .在 2— 5nm的尺寸范围内 ,纳米硅发光中心上的载流子复合概率远大于内部复合概率 ,仅需考虑发光中心上的载流子复合发光 .还发现发光中心与纳米硅粒子间的内电场对于纳米硅的发光峰位振荡有着显著的影响 .发光中心与纳米硅粒子间的内电场的存在会显著减小纳米硅粒子的内部发光效率以及外部相应发光中心上的发光强度。

关键词：内电场纳米硅光致发光谱量子限制发光中心载流子复合率发光强度