Surface And Interface Phonon Polaritons In Quantum Well Wire Systems Consisting Of Ternary Mixed Crystals

Low-dimension semiconductor nanomaterials have wide applications in artificial optical and electronic devices, and characteristics of surface and interface phonon polaritons are very important to understand the optical properties of low-dimensional semiconductor systems, so surface and interface phonon polaritons in low-dimensional semiconductor systems become one of hot points. The interface phonon polariton (IPP) have been investigated in heterostructure and quantum well wire systems consisting of polar ternary mixed crystal (TMC) with the modified random-element-isodisplacement (MREI) model and the Born-Huang approximation, applied the Maxwell’s equations and the boundary condition of electromagnetic field.1. Interface phonon polaritons in the heterostructure systems GaAs/AlxGa1-xAs and GaN/GaxIn1-xN consisting of polar ternary mixed crystal have been investigated. The numerical results of the IPP modes frequencies as functions of the wave-vector and composition x are obtained and analyzed. It is shown that there are three branches of IPP modes in heterostructure systems, and the frequencies of IPP modes non-linear change with the composition.2. For the rectangular quantum well wires(RQWW) systems GaAs/AlxGa1-xAs and Znxd1-xSe/ZnSe, the numerical results of the frequencies of IPP modes as functions of the wave-vector, cross-section aspect ratio, as well as composition x are gained. It is shown that there are six branches of IPP modes in RQWW system. The IPP modes are extremely sensitive to the change of geometric structure of RQWW and component of TMC.3. For the freestanding quantum well wire(FQWW) systems GaAs/AlxGa1-xAs and Znxd1-xSe/ZnSe, we gained and discussed the numerical results of the surface and interface phonon polariton(SPP and IPP) modes as functions of the wave-vector, the thickness ratio, as well as composition x. It is shown that there are six branches of IPP modes and four branches of SPP modes in GaAs/Al0.25Ga0.75quantum well wire systems, however, in Zno.25Cdo.75Se/ZnSe quantum well wire systems, there are six branches of IPP modes and two branches of SPP modes. The IPP modes are more sensitive to the thickness ratio than SPP modes.