Spin-phonon interactions of multiferroic Bi4Ti3O12-BiFeO3 ceramics: Low-temperature Raman scattering and infrared reflectance spectra investigations

Abstract

Optical phonons of multiferroic Bi 4 Ti 3 O 12 -BiFeO 3 ceramic have been investigated by low temperature Raman scattering and infrared reflectance spectra. Anomalies at about 85 K can be observed from the temperature dependence of the Raman and infrared modes, which arise from spin-phonon interaction during antiferromagnetic to paramagnetic phase transition. It was found that the change of exchange interaction in magnetic phase transition can be induced by Fe-O-Fe octahedral tilting driven from the A-site atoms. Moreover, ferroelectricity-related displacement of Bismuth atoms suggests the coupling of magnetic and ferroelectric orders. V C 2014 AIP Publishing LLC.

Lattice assisted dielectric relaxation in four-layer Aurivillius Bi5FeTi3O15 ceramic at low temperatures

“…Our results explain the anomalous temperature dependence of Raman and IR modes at around 85 K, as reported in literature for BFTO [34]. However, the authors interpreted the results in terms of the spin-phonon coupling in BFTO.…”

“…The effect of temperature on modes is shown by arrows in figure 6. The modes in this region are mostly related to the vibration of O atoms in the (Fe/Ti)O 6 octahedra and change in the bond distance between Bi atom of Bi 2 O 2 layer and O atom of perovskite slab [33,34]. The first two components account for 80% of the total variance: ≈55% for PC1 and ≈25% for PC2, respectively.…”

Exploring optoelectronic properties and mechanisms of layered ferroelectric K4Nb6O17 nanocrystalline films and nanolaminas

“…IR reflectance spectroscopy is an attractive and powerful tool for optical characterization of semiconductor materials 44, 45 . Thus, the combined use of both two techniques could further investigate the structural features of KN.…”

Hole conduction and electro-mechanical properties of Na0.5Bi2.5Ta2O9-based piezoelectric ceramics with the Li+/Ce3+/Sc3+ modification

“…24 The modes locating at low frequency range (below 200 cm À1 ) should be dominated by the vibrations of the A-site ions, while the modes above 200 cm À1 are mainly originated from the TaO 6 octahedra. [30][31][32][33] In Fig. 2(b), the mode at $110 has a change in frequency and intensity due to the Li þ /Ce 3þ /Sc 3þ introduction.…”