Interface optical phonons in spherical multilayer nanostructures

✍ Scribed by López, I. ;Kanyinda-Malu, C. ;de la Cruz, R. M.

• Book ID: 105363694
• Publisher: John Wiley and Sons
• Year: 2006
• Tongue: English
• Weight: 636 KB
• Volume: 203
• Category: Article
• ISSN: 0031-8965
• DOI: 10.1002/pssa.200566112

✦ Synopsis

Abstract

Within the dielectric continuum model, we calculate the interface phonons in multilayered spherical nanostructures. The effect of the alloying in the shell material, together with the change in the embedding medium are also analyzed. In all investigated heterostructures, the interface characteristics experiment a constantlike tendency at critical geometrical parameter g ~c~, whose values are sensitively determined by the ratio between dielectric constants of constitutive materials. We observe that the asymptotic limiting interface frequencies slightly depend on the embedding medium. For special cases, the high‐index phonon branches cross each other for specific values of geometrical parameter g . This crossing‐over critically depends on the core‐to‐shell dielectric constants ratio and on the type of host material. Also, we observe that the presence of Ga‐impurity in the shell material makes the highest shell‐like modes independent both on the geometrical parameter g and on the orbital index l . (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)