Document Type

Article

Publication Date

5-15-2002

Keywords

LOW-DIMENSIONAL SYSTEMS, PHONON MODES, SEMICONDUCTOR MICROCRYSTALLITES, LATTICE-DYNAMICS, ANB8-N COMPOUNDS, SCATTERING, NANOCRYSTALS, CONFINEMENT, CDSE, SHIFTS, Physics

Abstract

Raman intensities of Si quantum dots (QD's) with up to 11489 atoms (about 7.6 nm in diameter) for different scattering configurations are calculated. First, phonon modes in these QD's, including all vibration frequencies and vibration amplitudes, are calculated directly from the lattice-dynamic matrix by using a microscopic valence force field model combined with the group theory. Then the Raman intensities of these quantum dots are calculated by using a bond-polarizability approximation. The size effects of the Raman intensity in these QD's are discussed in detail based on these calculations. The calculations are compared with the available experimental observations. We are expecting that our calculations can further stimulate more experimental measurements.

Comments

This article is the copyright property of the American Physical Society and may not be used for any commercial or other private purpose without specific written permission of the American Physical Society.

Share

COinS