Phase transformations in multiferroic Bi{sub 1−x}La{sub x}Fe{sub 1−y}Ti{sub y}O{sub 3} ceramics probed by temperature dependent Raman scattering

Journal Article · Tue Oct 28 04:00:00 EDT 2014 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4900439· OSTI ID:22308175

Xu, L. P.; Zhang, X. L.; Zhang, J. Z.; Chu, J. H. ^[1]; Zhang, L. L.; Yu, J. ^[2]

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1. Key Laboratory of Polar Materials and Devices, Ministry of Education, Department of Electronic Engineering, East China Normal University, Shanghai 200241 (China)
2. Functional Material Research Laboratory, Tongji University, Shanghai 200092 (China)

Optical phonons and phase transitions of Bi{sub 1−x}La{sub x}Fe{sub 1−y}Ti{sub y}O{sub 3} (BLFTO, 0.02 ≤ x ≤ 0.12, 0.01 ≤ y ≤ 0.08) ceramics have been investigated by Raman scattering in the temperature range from 80 to 680 K. Four phase transitions around 140, 205, 570, and 640 K can be observed. The Raman modes are sensitive to the spin reorientation around 140 and 205 K, owing to the strong magnon-phonon coupling. The transformation around 570 K is a structural transition from rhombohedral to orthorhombic phase due to an external pressure induced by the chemical substitution. The anomalies of the phonon frequencies near Néel temperature T{sub N} have been discussed in the light of the multiferroicity. Moreover, it was found that the structural transition temperature and T{sub N} of BLFTO ceramics decrease towards room temperature with increasing doping composition as a result of size mismatch between substitution and host cations.

• OSTI ID: 22308175
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 16 Vol. 116; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BISMUTH COMPOUNDS
CERAMICS
IRON COMPOUNDS
LANTHANUM COMPOUNDS
NEEL TEMPERATURE
ORTHORHOMBIC LATTICES
PHASE TRANSFORMATIONS
PHONONS
RAMAN EFFECT
SPIN
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0273-0400 K
TITANATES
TRANSFORMATIONS
TRANSITION TEMPERATURE
TRIGONAL LATTICES
VISIBLE RADIATION