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https://hdl.handle.net/1822/5461
Título: | Dipolar vibrational modes in spherical semiconductor quantum dots |
Autor(es): | Vasilevskiy, Mikhail |
Palavras-chave: | Phonons Quantum dots Lattice dynamics Dielectric function FIR spectroscopy |
Data: | 2002 |
Editora: | American Physical Society |
Revista: | Physical Review B (Condensed Matter) |
Citação: | "Physical Review B (Condensed Matter)". ISSN 0163-1829. 66 (2002) 195326:1-195326:9 |
Resumo(s): | Spatially quantized dipolar phonon modes in a spherical quantum dot ~QD! made of a polar isotropic material are considered in the framework of a continnum model. Different mechanical boundary conditions are analyzed, which are shown to strongly influence the spectrum of the dipole-active modes. The phonon-related polarizability of a single QD and an average dielectric function of a composite containing QDs are calculated. Numerical results are presented for CdSe and InP dots. A strongly dipole-active gap mode is predicted for InP QDs embedded in a matrix with a defined range of dielectric constant. The effect of increasing QD concentration in ensembles is discussed in terms of the dipole–dipole interaction between the dots, which can result in their bulk-like FIR absorption spectra with a peak at the transverse optical ~TO! phonon frequency instead of the Fro¨hlich frequency. It is suggested that similar effects might occur in individual microcrystals, which can explain their absorbtion of FIR radiation at the TO phonon frequency, despite having a size much smaller than the radiation wavelength. |
Tipo: | Artigo |
URI: | https://hdl.handle.net/1822/5461 |
DOI: | 10.1103/PhysRevB.66.195326 |
ISSN: | 0163-1829 |
Arbitragem científica: | yes |
Acesso: | Acesso aberto |
Aparece nas coleções: | CDF - CEP - Artigos/Papers (with refereeing) CDF - FMNC - Artigos/Papers (with refereeing) |
Ficheiros deste registo:
Ficheiro | Descrição | Tamanho | Formato | |
---|---|---|---|---|
PRB2002.pdf | Documento principal | 196,67 kB | Adobe PDF | Ver/Abrir |
Erratum_PRB2002.pdf | Erratum | 32,78 kB | Adobe PDF | Ver/Abrir |