Low frequency phonons in nanoparticles
نویسنده
چکیده
The consequence of the phonon confinement on the phonon spectra particularly the low frequency spectra in nanocrystal quantum dots has been investigated. Due to the phonon confinement effect, there appears spheroidal and quadrupolar modes of nanoparticles in the low frequency spectra. The frequency of these modes increases with the decrease of the size of the nanocrystal quantum dot (nanoparticle). The effect of surrounding medium on the phonon spectra of the nanoparticles, which is observed as the broadening of the phonon line shape due to the acoustic mismatch at the surface of the nanoparticles has also been discussed. The effect of density of the surrounding medium on the phonon modes has been discussed and the results on the damping constant and quality factor have been studied.
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