Anomalous Lattice Dynamics of EuSi_{2} Nanoislands: Role of Interfaces Unveiled

Autor: A, Seiler, P, Piekarz, S, Ibrahimkutty, D G, Merkel, O, Waller, R, Pradip, A I, Chumakov, R, Rüffer, T, Baumbach, K, Parlinski, M, Fiederle, S, Stankov
Rok vydání: 2016
Zdroj: Physical review letters. 117(27)
ISSN: 1079-7114
Popis: We report a systematic lattice dynamics study of EuSi_{2} films and nanoislands by in situ nuclear inelastic scattering on ^{151}Eu and ab initio theory. The Eu-partial phonon density of states of the nanoislands exhibits anomalous excess of phonon states at low and high energies, not present in the bulk and at the EuSi_{2}(001) surface. We demonstrate that atomic vibrations along the island-substrate interface give rise to phonon states both at low and high energies, while atomic vibrations across the island-island interface result in localized high-energy phonon modes.
Databáze: OpenAIRE