Phonon spectrum in a nanoparticle mechanically coupled to a substrate
نویسندگان
چکیده
We calculate the vibrational density-of-states in an insulating nanoparticle that is in weak mechanical contact with a semi-infinite substrate. The work is motivated by a recent experiment by Yang et al., where the low-energy phonon density-of-states of Y2O3 nanoparticles doped with Eu 3þ was measured. Preliminary results presented here, based on the conventional quasiparticle-pole approximation for the phonon propagator, are in reasonable agreement with experiment. r 2001 Elsevier Science B.V. All rights reserved. PACS: 63.22.+m; 78.66.Vs
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Phonons in a nanoparticle mechanically coupled to a substrate
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