Optical vibration modes in spherical multilayer nanostructures

Using the dielectric continuum approach, we study the optical vibration modes in a polar spherical multilayer nanostructure hosted in a non-polar material. The dispersion relation and the corresponding electron–phonon interaction Hamiltonians for interface optical (IO) or surface optical (SO) phonons are derived. As a typical case, the numerical results for the CdSe/ZnS/CdSe spherical multilayer nanostructure are given. The frequency and electric potential characteristics of 5 branches of IO/SO phonon modes are analyzed. The results show that the electron–phonon coupling related to the IO modes with higher frequencies and the SO modes are more significant.