线度和势垒宽度对球状纳米系统电子散射截面的影响  

Influences of the size and breadth of potential barrier on electronic scattering cross-section in spherical nanometer system

作　　者：吴强[1] 郑瑞伦[1] 

机构地区：[1]重庆文理学院电子电气工程学院,重庆402160

出　　处：《物理学报》2011年第12期497-502,共6页Acta Physica Sinica

基　　金：重庆文理学院引进人才计划(批准号:Z2011RCYJ03);重庆市教育委员会科学技术研究基金(批准号:KJ101206)资助的课题~~

摘　　要：在有效质量近似和球形方形势模型下,计算了开放型球状纳米系统电子散射截面及电子按能量的概率分布,探讨了线度、势垒宽度对电子散射截面和共振能量以及共振宽度的影响.结果表明:电子的散射截面随能量的分布曲线有一极大值和极小值,而且电子能量的概率分布曲线的极大值位置总是介于散射截面分布曲线的极大值与极小值的能量位置之间;散射截面随内核半径r0的增大而增大,而且散射截面分布曲线随r0的增大由较平滑变得较尖锐;散射截面随势垒宽度Δ的增大而增大,但在Δ=1.4aCdS—1.7aCdS的范围内,变化出现异常,在Δ=1.6aCdS时散射截面出现极小;电子共振能量El随Δ的变化与电子所处状态有关,而电子共振宽度Γl随Δ的增大而减小;不论Δ取何值,El和Γl都满足能量和时间的测不准关系.Under the condition of the spherical square potential model and the effective mass approximation,the electronic scattering cross-section and the electronic probability distribution are obtained in an open-type spherical nanometer system,and the influences of the size and the width of potential barrier on electronic scattering cross-section,resonance energy and resonance width are discussed.The results show that there exist one maximum and one minimum in the distribution curve of the electronic scattering cross-section versus energy,and the maximum of electronic energy probability distribution curve is between the maximum and the minimum of energy in the scattering cross-section curve;the scattering cross-section increases with the increase of r0,the inner radius,and the scattering cross-section curve will change from smoother to sharper with the increase of r0;the scattering cross-section will enlarge with Δ,the width of potential barrier,but it will become abnormal when Δ is between 1.4aCdS and 1.7aCdS;when Δ=1.6aCdS,the scattering cross-section is extremely small;El,the electronic resonance energy changing with Δ,is related to the electronic state,while Γl,the electronic resonance width will decrease with the increase of Δ;no matter what Δ is,both El and Γl satisfy the uncertainty principle of energy and time.

关 键 词：球状纳米系统 势垒宽度 电子散射截面 电子概率分布 

分 类 号：TB383.1[一般工业技术—材料科学与工程]