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arXiv · 0709.0848

Infrared phonon dynamics of multiferroic BiFeO3 single crystal

R. P. S. M. Lobo·R. L. Moreira·D. Lebeugle·D. Colson
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Abstract

We discuss the first infrared reflectivity measurement on a BiFeO3 single crystal between 5 K and room temperature. The 9 predicted ab-plane E phonon modes are fully and unambiguously determined. The frequencies of the 4 A1 c-axis phonons are found. These results settle issues between theory and data on ceramics. Our findings show that the softening of the lowest frequency E mode is responsible for the temperature dependence of the dielectric constant, indicating that the ferroelectric transition in BiFeO3 is soft-mode driven.

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R. P. S. M. Lobo, R. L. Moreira, D. Lebeugle, D. Colson. 2007-09-06. Infrared phonon dynamics of multiferroic BiFeO3 single crystal. https://doi.org/10.1103/physrevb.76.172105

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