Transfer Matrix Method Solving Interface Optical Phonons In Wurtzite Core-Multishell Nanowires Of ?-Nitrides

Wurtzite GaN and its ternary mixed crystal are widely used in photoelectric devices of which photoelectric properties can be improved by controlling its composition.Core-shell nanowires(CSNWs)have application prospect in nanoscale photoelectric systems due to the high integration,reduction of short channel effect and high electron mobility by reducing the surface defects.Core-multishell nanowires(CMSNWs)are common functional units in light emitting diodes,solar cells and transistors.The interaction between electrons and interface optical phonons(IOPs)plays an important role to affect optoelectronic properties in low dimensional systems.This work will discuss transfer matrix method(TMM)solving interface optical phonons in wurtzite core-multishell nanowires.In this thesis,based on dielectric continuum and Loudon's uniaxial crystal models,characteristics of IOPs in CMSNWs are investigated by TMM.The possible IOPs satisfying exiting conditions,as well as its dispersion relations and electro-static potentials in wurtzite GaN/InxGa1-xN/InyGa1-yN and GaN/InxGa1-xN/InyGa1-yN/InzGa1-zN CMSNWs are discussed as examples.The results show that TMM for IOPs is available in CMSNWs.An IOP is classified by the possible combinations of the interface here and its characteristics are as follows:(1)There are certain types of IOPs with certain frequency regions in CMSNWs for a given component.(2)The dispersion relations of IOPs in CMSNWs is found to be the combination of that in each nearest two layer of CSNW.It can explain the fact that the total branch number of IOPs obey the 2n rule.(3)It is also found that the peak positions of electro-static potentials are decided by the layer component order from the inner to outside layer in CMSNWs.Based on this method,one can further discuss the IOPs related photoelectric properties in nitride CMSNWs.