G.F. Yuan
,
C.S. Ge
,
X.Y. Zeng
金属学报(英文版)
The physical model of temperature field and thermal stress field are established in this
paper, on which the numerical simulation with the assuming physical and laser milling
parameters have been finished. The laser milling process can be explained.
关键词:
laser milling
,
null
,
null
Applied Physics Letters
Amorphous Ge1-xSx(x=0.61, 0.67, and 0.72) semiconductor alloys have been found formed by ball milling of powder mixtures of elemental Ge and S. The amorphization process and the ball-milled products have been investigated by x-ray diffraction, transmission electron microscopy, and Raman scattering. The results show that amorphous Ge-S alloys may form in a self-heating reaction, driven by the large heat of formation of amorphous and/or liquid Ge-S alloys. The structure of mechanically alloyed amorphous Ge-S alloys is similar to but not exactly identical with that of rapidly cooled amorphous Ge-S alloys. The amorphization transition mechanism reported is believed to be suitable for preparing other amorphous semiconductor alloys with similar thermodynamic conditions.
关键词:
magnetic-properties;ni-zr;amorphization;powders;transition;interdiffusion;germanium;systems;glasses;metals
顾少轩
,
胡海平
,
赵修建
硅酸盐通报
doi:10.3969/j.issn.1001-1625.2006.01.019
采用熔融-急冷法制备CdS掺杂Ge-Ga-S硫系玻璃,对玻璃的XPS研究表明:玻璃样品中含有Ge,Ga,Cd,S 4种元素,样品的主要成分是GeS2,Ga2S3和CdS;Ge,Ga,Cd,S元素的XPS谱线的位移归因于化学位移和玻璃的结构的共同作用;Cd3d3/2和Cd3d5/2的XPS峰值随CdS含量的增加而明显增强.
关键词:
熔融-急冷法
,
Ge-Ga-S硫系玻璃
,
XPS
Journal of Physics-Condensed Matter
Crystalline C, Si and Ge in a lonsdaleite (hexagonal diamond) structure are studied by plane-wave pseudopotential calculations in the scheme of density-functional theory and the local density approximation. The same calculations with generalized gradient corrections and also for the cubic diamond phases of these elements are also performed for comparison. Our results show that the bulk moduli are quite similar between the diamond and lonsdaleite polytypes of these elements. The theoretical bulk modulus of lonsdaleite C is 0.2-0.3% higher than diamond. It is expected to replace diamond as the hardest material in the world. The LDA result shows lonsdaleite Ge as a semimetal for its zero band gap at its Gamma point. Considering the exchange-correlation energy correction, it is estimated that lonsdaleite Ge is a semiconductor with a small direct band gap.
关键词:
diamond hexagonal silicon;total-energy calculations;plane-wave;electronic-structure;pseudopotentials;semiconductors;germanium;pressure;microscopy;defects
李伟文
,
赵新兵
,
邬震泰
,
曹高劭
功能材料
对掺C和Ge的Fe-Su-Si-Mn基热电材料的电学性能研究表明,相对于未掺的Fe-Si-Mn基热电材料,掺C样品的电阻率降低,但热电动势率增加.掺Ge样品的电阻率有所升高,但热电动势率增加更快,因此掺C、Ge样品有较高的功率因子,比未掺样品提高近1倍.
关键词:
热电材料
,
FeSi2
,
电学性能
,
掺杂
沈海军
,
付光俊
,
陈裕
功能材料与器件学报
doi:10.3969/j.issn.1007-4252.2006.06.018
采用扩展的Hückel方法与格林函数方法,分析了双Au电极作用下,C60、Si@C60以及Ge@C60富勒烯分子的电子结构与导电性,并对三种富勒烯分子的电子结构与电子输运特性进行了对比.研究结果表明,C60、Si@C60或Ge@C60分子与Au电极"接触"后,其最高占据分子轨道与最低未占据分子轨道间的能隙减小,它们与Au电极之间的结合既有共价键的成分,又有离子键的成分;三种富勒烯分子的电子输运性能依次具有Ge@C60＞Si@C60＞C60的顺序.
关键词:
C60富勒烯分子
,
Hückel方法
,
格林函数
,
电子结构
,
电子传输
朱军
,
戴世勋
,
彭波
,
徐铁峰
,
王训四
,
章向华
无机材料学报
doi:10.3724/SP.J.1077.2010.00546
采用熔融冷却法制备了系列不同Ho3+离子掺杂浓度的Ge-Ga-S-CsI玻璃样品,测试了样品的折射率、吸收光谱以及中红外荧光光谱和Ho3+离子5I6能级荧光寿命.应用Judd-Ofeh理论计算了Ho3+离子在该基质玻璃中强度参数Ωi(i=2,4,6)、能级跃迁振子强度fcal、自发跃迁几率Arad等光谱参数.计算了Ho3+:5I5→5I6(3.86μm)和5I6→5I7(2.81μm)跃迁的多声子驰豫速率.讨论了中红外荧光特性与Ho3+离子掺杂浓度之间的关系.结果表明,在900nm激光泵浦下观察到了2.81和3.861μm两处中红外荧光,分别对应于Ho3+:5I6→5I7和5I5→5I6跃迁,当Ho3+离子掺杂浓度从0.5wt%增加到1.0wt%时,两处中红外荧光强度都随相应增加,计算的Ho3+:5I5→5I6和5I6→5I7跃迁多声子驰豫速率分别为29s-1和34s-1.
关键词:
中红外发光
,
硫系玻璃
,
钬离子
刘鹏强
,
王茺
,
周曦
,
杨杰
,
杨宇
功能材料
doi:10.3969/j.issn.1001-9731.2014.05.012
采用离子束溅射技术,通过改变诱导量子点形成的C层生长温度,在n型Si(100)衬底上自组装生长了一系列Ge量子点。利用 AFM和 Raman光谱对样品的表面形貌和结构进行了表征。实验结果表明,当C层的温度从600℃升高到700℃时,Ge 量子点的密度逐渐降低,且结晶性变差；此时,量子点中的 Si 组分升高。当C层的生长温度从700℃升高到800℃过程中,Ge量子点的密度逐渐增大,结晶性也有所改善；此时,量子点中的Si含量降低。
关键词:
离子束溅射
,
Ge量子点
,
扩散
,
C诱导
