The surface acoustic phonon modes arising from 1:1 ordered, charged nanoclusters and the charge compensating disordered shells were analyzed in relaxor ferroelectric perovskite lead magnesium niobate (PMN). The size of the 1:1 ordered, charged nanocluster from the x-ray diffraction was estimated to be about 2nm. Surface acoustic Raman modes were detected in the frequency range 5-25 cm-1. The low frequency modes arised from two different interfaces, one between the 1:1 ordered charged nanoclusters and the surrounding positively charged nanoshell and another between the nanoshell and the outer disordered cubic phase of PMN.

Venkatachalam Subramanian

Department Of Physics

Ferroelectric materials

Frequencies

Light polarization

Nanostructured materials

Perovskite

Phase composition

Phase Transitions

Raman scattering

CHARGE COMPENSATION

Nanoclusters

RAMAN MODES

SURFACE ACOUSTIC PHONONS

Phonons

Fulltext

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IIT Madras

Study of surface acoustic phonon modes in relaxor Pb(Mg1∕3Nb2∕3)O3

Applied Physics Letters

The temperature dependence of the photoluminescence spectra of the relaxor ferroelectric Pb(Mg1/3Nb2/3)O3 has been reported. The temperature behaviours of the 1.57, 1.67 and 1.73 eV bands indicate a phase transition at 110 K. This is attributed to a structural phase transition in the charged nanoshell. Analysis of the temperature dependence of 1.67 eV band intensity with a thermal quenching model indicated the existence of a phonon mode at 1153 cm-1. This mode is identified in the Raman spectra measurement. The intensity of the 1.73 eV band showing an anomalous behaviour at 210 K is attributed to a transition from a crystalline phase to an amorphous phase in the charged nanoshell. © 2007 Elsevier Ltd. All rights reserved.

Solid State Communications

Photoluminescence investigations on the nanoscale phase transition in Pb(Mg1/3Nb2/3)O3

Journal of the Physical Society of Japan

Raman Scattering in (1-x)Pb(Mg1/3Nb2/3)O3–xPbTiO3

Ferroelectrics

PbMg1/3Nb2/3O3as a model object for light scattering experiments

Journal of Applied Physics

Raman spectroscopic study of order–disorder in lead magnesium niobate

Journal of Solid State Chemistry

Numerical Determination of the Local Ordering of PbMg1/3Nb2/3O3 (PMN) from High Resolution Electron Microscopy Images

Size of Cd(S,Se) quantum dots in glasses: Correlation between measurements by high‐resolution transmission electron microscopy, small‐angle x‐ray scattering, and low‐frequency inelastic Raman scattering

Study of surface acoustic phonon modes in relaxor Pb(Mg 1/3Nb2/3)O3

Journal	Applied Physics Letters
ISSN	00036951
Open Access	No