基底对离子束与层状二维电子气作用的影响  

Effect of substrate on interactions of ion beams with two-dimensional layered electron gases

作　　者：菅阳阳 李春芝[1] 

机构地区：[1]内蒙古民族大学物理与电子信息学院,通辽028043

出　　处：《原子与分子物理学报》2014年第5期833-837,共5页Journal of Atomic and Molecular Physics

基　　金：国家自然科学基金(11005058);内蒙古民族大学研究生科研创新资助项目(10136201403);内蒙古自治区自然科学基金(2014MS0108);内蒙古民族大学科研创新团队资助项目

摘　　要：采用线性化量子流体动力学(Quantum Hydrodynamics QHD)模型和Poisson方程相结合,研究了离子束与存在基底的双层二维电子气平面相互作用时的静电激发现象.选择恰当边界条件,推导出相互作用过程中感应电子气密度、感应电势及阻止本领的一般表达式.结果表明,随着基底介电常数的增加,两个平面内的感应电子气密度以及空间感应电势振荡的波长明显变长.同时,由于两个电子气平面间的耦合作用,阻止本领随速度变化曲线出现明显的双峰结构,随着介电常数的增大,双峰结构逐渐消失.The electronic excitations induced by ion beams moving parallel to two -dimensional （2D） lay-ered electron gases supported by an insulating substrate are investigated by using linearized quantum hy-drodynamic （Q HD） model and Poisson equation .General expressions of the induced density of the elec-tron gases ,induced potential and stopping power are obtained by selecting the appropriate boundary con-ditions .The results show that the oscillatory wavelengths of perturbed electron gases density in two sheets and the spatial distribution of induced potential get longer obviously with the increase of dielectric constant of substrate .Meanwhile ,the changes of stopping power curves with the incident particle speed appear double peaks due to the coupling effects between the fields of both electric sheets ,and the double peaks gradually disappear with the increase of dielectric constant of substrate .

关 键 词：线性化QHD模型 层状二维电子气 介电常数 尾流效应 阻止本领 

分 类 号：O539[理学—等离子体物理]