Anharmonicity on Raman active phonon modes of LaAlO3

J. Suda, O. Kamishima, J. Kawamura, T. Hattori, T. Sato

Research output: Contribution to journalArticlepeer-review

12 Citations (Scopus)

Abstract

The phonon-dispersion relations of LaAlO3 crystal are calculated using the first-principle calculations. The first-order Raman spectra in the LaGaO3 were measured in the temperature range of 20-300K for the rhombohedral phase. The temperature dependence of the linewidth of the A lg (132 cm-1) and that of Eg (489 cm -1) were analyzed using temperature-weighted two-phonon density of states (TDOS) due to the cubic term. The calculated results reproduce the observed ones in this temperature range. The scattering of a thermal phonon by observed phonons dominates phonon-phonon interaction on the rotational modes [the Alg (132 cm-1)]. Phonon-phonon interaction on the bending mode [the Eg (489 cm-1)] is dominated by both the scattering and the decay of the observed phonons into two phonons having lower energies. We found that this originates in the discrete spectra on the higher-frequency side in the phonon density of states that produces a difference in anharmonic effects on each peak's channels in the HT. This result is similar to that in the high-temperature phase in the case of LaGaO3 [1].

Original languageEnglish
Article number052249
JournalJournal of Physics: Conference Series
Volume150
Issue number5
DOIs
Publication statusPublished - 2009

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Anharmonicity on Raman active phonon modes of LaAlO<sub>3</sub>'. Together they form a unique fingerprint.

Cite this