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arXiv · 0909.3889

Ferroelectric Soft Mode in Pb(Mg1/3Nb2/3)O3

Hiroki Taniguchi·Masanori Oishi·Desheng Fu·Mitsuru Itoh
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Abstract

Ferroelectric soft mode in Pb(Mg1/3Nb2/3)O3 (PMN) has been clearly resolved by precision Raman scattering measurements for the first time. A polarization direction of the incident laser was chosen along [110] in cubic configuration in order to eliminate strong scattering components around 45 cm-1, which always smeared the low-frequency spectra of PMN. The soft mode frequency omega_s (=\sqrt{omega_0^2-gamma^2}) softens around 200 K, where omega_0 and gamma are a harmonic frequency and a damping constant, respectively. The present result evidenced that the origin of the polarizationthe in PMN is the soft mode.

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Hiroki Taniguchi, Masanori Oishi, Desheng Fu, Mitsuru Itoh. 2009-09-22. Ferroelectric Soft Mode in Pb(Mg1/3Nb2/3)O3. https://arxiv.org/abs/0909.3889

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