Raman study of phonon anharmonicity in LaF3

Liarokapis, E; Anastassakis, E; Kourouklis, GA

dc.contributor.author	Liarokapis, E	en
dc.contributor.author	Anastassakis, E	en
dc.contributor.author	Kourouklis, GA	en
dc.date.accessioned	2014-03-01T01:06:28Z
dc.date.available	2014-03-01T01:06:28Z
dc.date.issued	1985	en
dc.identifier.issn	01631829	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/9403
dc.title	Raman study of phonon anharmonicity in LaF3	en
heal.type	journalArticle	en
heal.identifier.primary	10.1103/PhysRevB.32.8346	en
heal.identifier.secondary	http://dx.doi.org/10.1103/PhysRevB.32.8346	en
heal.publicationDate	1985	en
heal.abstract	The first-order Raman spectrum of LaF3 was studied as a function of hydrostatic pressure (010 GPa) and temperature (60900 K). The calculated values for the mode Gr̈neisen parameters are between 1 and 2, in reasonable agreement with those derived from uniaxial-stress experiments. Deviations from the isotropic approximation, in handling the temperature dependence of the long-wavelength optical-phonon frequencies, are found to be smaller than 15%. Anharmonicity contributions to the phonon frequencies and half-widths are calculated from the joint data. The results indicate that for most of the phonons it is the volume contributions that are mainly responsible for the temperature-induced frequency shifts. Anharmonicity appears to be important for fewer phonons and also for the increase of linewidth with temperature for all phonons studied. Other observations are also discussed, such as the pressure dependence of the phonon linewidths and the frequency dependence of the frequency-versus-pressure slopes. © 1985 The American Physical Society.	en
heal.journalName	Physical Review B	en
dc.identifier.doi	10.1103/PhysRevB.32.8346	en
dc.identifier.volume	32	en
dc.identifier.issue	12	en
dc.identifier.spage	8346	en
dc.identifier.epage	8355	en