[en] The entire zone-center phonon spectrum of the R3c ferroelectric antiferromagnetic phase of bismuth ferrite is computed using a first-principles approach based on density functional theory. Two phonon modes exhibiting eigendisplacement vectors that strongly overlap with the atomic distortions taking place at the ferroelectric structural phase transition are identified and give support to a transition with displacive character. Both Raman and infrared reflectivity spectra are also computed, providing benchmark theoretical results for the assignment of experimental spectra.
Disciplines :
Physics
Author, co-author :
Hermet, Patrick ; Université de Liège - ULiège > Département de physique > Physique théorique des matériaux
Goffinet, Marco ; Université de Liège - ULiège > Département de physique > Physique théorique des matériaux
Kreisel, J.
Ghosez, Philippe ; Université de Liège - ULiège > Département de physique > Physique théorique des matériaux
Language :
English
Title :
Raman and infrared spectra of multiferroic bismuth ferrite from first principles
Publication date :
2007
Journal title :
Physical Review. B, Condensed Matter and Materials Physics
ISSN :
1098-0121
eISSN :
1550-235X
Publisher :
American Physical Society, Woodbury, United States - New York