机构地区: 内蒙古大学物理科学与技术学院
出 处: 《内蒙古大学学报(自然科学版)》 2008年第4期401-406,共6页
摘 要: 采用改进的无规元素等位移模型和玻恩-黄近似,运用电磁场的麦克斯韦方程和边界条件,研究了薄膜厚度对由极性三元混晶组成的双层薄膜系统中的表面和界面声子极化激元的影响.以GaAs/AlxGa1-xAs双层系统为例,获得了其中表面和界面声子极化激元作为膜厚之函数的数值结果并进行了讨论.结果指出:在双层系统的六支表面和界面声子极化激元模中,当两种薄膜材料的厚度均变化时,只有三支界面声子极化激元的频率随之变化,而另外三支表面声子极化激元的频率则几乎不变.而当只有其中一种薄膜材料的厚度发生变化时,则只对其与另一种薄膜材料界面处且位于此种材料的纵横光学声子频率区间内的界面极化激元的频率有影响,而对其他的表面和界面极化激元的频率则没有太大的影响. The surface and interface phonon-polaritons in bilayer systems consisting of polar ternary mixed crystals are investigated in the modified random-element-isodisplacement model and the Born-Huang approximation,based on the Maxwell's equations with the boundary conditions.The numerical results of the surface and interface phonon-polariton frequencies as functions of the thicknesses of the slabs in GaAs/AlxGa1-xAs bilayer systems are obtained and discussed.It is shown that there are six branches of surface and interface phonon-polaritons in binary/ternary systems.The energies of the three interface phonon-polaritons increase with the increase of the thicknesses of the bilayer system,but those of the other three surface modes change hardly with the varieties of the thicknesses of the system.Moreover,the energies of the interface phonon-polaritons,which localized in the frequency regions between the longitudinal optical and transverse optical phonons of the slab material,increase with the increase of the thickness of single slab in the bilayer systems,whereas the rest of the surface and interface modes almost keep less influence.
关 键 词: 表面和界面声子极化激元 三元混晶 双层薄膜系统