材料期刊网

THE STABILITY INVESTIGATION OF FERROELECTRIC SrBi2Ta2O9 THIN FILMS ANNEALED IN FORMING GAS

T.Yu , D.S.Wang , D.Wu

金属学报(英文版)

The hysteresis loop changes of ferroelecric SrBi2 Ta2 O9 (SBT) thin films (330nm) vsthe temperature of forming gas (5%o hydrogen+95%o nitrogen) annealing were measuredwhen the annealing time was 1min and 10min. The selected annealing temperaturewas at 100℃, 200℃, 250℃, 300℃, 350℃, 400℃ and 4S0℃, respectively. Our resultsshowed that the ferroelectric properties were easily destroyed and the leakage currentchanged abruptly when the SBT thin films were in their ferroelectric phase (＜270℃).The space charges at the grain boundary may take an important role in absorptionpolarity molecular hydrogen when the SBT thin films were in the ferroelectric phase.The oxygen recovery experiments were also performed and investigated in this work.

关键词: ferroelectric , null , null , null

S-D系统的统一模型与稀磁合金的电子比热

陈丽 , 韩福祥

低温物理学报 doi:10.3969/j.issn.1000-3258.2000.01.013

本文采用Anderson s-d混合模型和s-d交换模型,讨论了磁性杂质溶入金属后,对稀磁合金比热的影响,并对Cd-Mn合金进行了定量的讨论.

关键词:

铁基超导体Minimum模型中的d波和扩展s波

车玮玮 , 苏希玉 , 王梅

低温物理学报

对比研究了Minimum模型中d-波配对和扩展s-波配对的基本性质.结果表明,超导序参量按类BCS关系随温度变化,重整化参数t对超导有抑制作用,当t足够大时,超导消失,系统进入正常金属相.此外,讨论了超导序参量随不同参量的变化关系.对于d波,系统有稳定态;而对于扩展s波,系统则没有稳定态.

关键词: Minimum模型 , d-波 , 扩展s-波 , 铁基超导体

Two-step magnetization in a spin-chain system on the triangular lattice: Wang-Landau simulation

Physical Review B

The Wang-Landau algorithm is used to study the thermodynamic and magnetic properties of triangular spin-chain system based on two-dimensional Ising model in order to understand the magnetic-order dynamics in Ca(3)Co(2)O(6) compound. The calculated results demonstrate that the equilibrium state of the rigid spins produces the two-step magnetization curve at low temperature even when the random-exchange term is considered. This work indicates that the four-step magnetization behavior observed experimentally must be due to the nonequilibrium magnetization.

关键词: calcium compounds;exchange interactions (electron);Ising model;magnetisation;thermodynamics;one-dimensional ca3co2o6;density-of-states;compound ca3co2o6;phase-diagram;proteins;crystal

同位旋效应对F同位素s-d能级间隙的影响

郭艳青 , 任中洲

原子核物理评论

在单粒子势模型的框架下,计算了O同位素和F同位素的基态和某些低激发态的能级值、均方根半径值及密度分布.通过在伍兹-萨克逊势中引入同位旋依赖项,研究了同位旋效应对F同位素s-d能级间隙的影响.理论计算得到的均方根半径值和自旋宇称值与实验结果一致.尤其是,理论计算能够实现16F,15F和14F中2s1/2与1d5/2质子能级间的反转,且F同位素中s-d质子能级间隙及其整体变化趋势与已知实验结果符合较好.此外,理论结果表明12F的(1/2)+第一激发态为单质子晕态.

关键词: 同位旋效应 , 能级反转 , 质子晕

A possible mechanism for quasi-two-dimensional ferromagnetism: The spectrum gap induced by s-d exchange interaction

Journal of Physics-Condensed Matter

A quasi-two-dimensional magnetic system is studied in which magnetic atoms are confined in the two-dimensional plane but the conduction electrons are in fact three-dimensional. By virtue of spin-wave theory, we find that a spectrum gap can be formed at the bottom of the spin-wave spectrum, induced by the s-d exchange interaction between conduction electrons and magnetic localized electrons. Thus, a new possible mechanism is proposed for two-dimensional ferromagnetic order at finite temperature.

关键词: ultrathin films;magnetoresistance;superlattices;magnetization;anisotropy;magnetism

S-D系统的统一模型与稀磁合金的热导率和热电势

陈丽

低温物理学报 doi:10.3969/j.issn.1000-3258.2001.02.012

本文采用Anderson s-d混合模型和s-d交换模型，讨论了磁性杂质溶入金属后，对稀磁合金热导率和热电势的影响，并对Cd-Mn合金进行了定量的讨论.

关键词:

D2、M2、S5模具扁钢脱碳特性实验研究

赵德文 , 郭长武 , 刘相华 , 王国栋 , 徐辉 , 戴建明

钢铁

开展了在空气和氮气两种气氛下，采用Gleeble-1500热模拟机与普通电炉两种加热方式、不同加热温度、加热时间对D2、M2、S5钢脱碳层深度影响的试验研究。依据试验结果，结合现场实际制定了较为合理的生产工艺并在现场成功应用，使上述模具扁钢脱碳层指标达到了美国ASTM-A681技术标准。

关键词: 脱碳层深度 , 模具扁钢 , ASTM-A681

基于DSP和S1D13305的EL屏显示控制系统设计

王兆伟 , 李士钊

液晶与显示 doi:10.3788/YJYXS20142903.0389

针对野外恶劣使用环境,设计了一种环境适应性强的显示控制系统.该系统采用基于DSP和S1D13305控制EL显示屏的设计方案,从软硬件两方面阐述了DSP和显示控制芯片之间的接口电路和设计方法,解决了显示控制芯片内部字库内容单一的问题,并给出了系统设置和显示控制芯片初始化程序,开发了显示驱动模块.经过实战考核和应用,该显示系统在野外恶劣环境中工作稳定,显示效果良好.该显示系统达到了预期效果.

关键词: 控制 , DSP , S1D13305 , EL显示屏

Cs-K混合蒸气中Cs(8D)+K(4S)碰撞能量转移

沈异凡 , 沈晓燕

量子电子学报 doi:10.3969/j.issn.1007-5461.2004.01.003

在Cs-K混合蒸气中,两步激发Cs原子到8D态,观察了Cs(8D)+K(4S)→Cs(5D)+K(4P)碰撞能量合并逆过程(REP,reverse energy pooling).应用双调制技术探测K(4P)原子发射的荧光,基态K原子密度用光学吸收方法测量.得到了REP速率系数,讨论了其它过程对速率系数的影响.

关键词: 光谱学 , 激发态原子 , 能量合并逆过程 , 速率系数