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Title: SrTiO{sub 3} Displacive Transition Revisited via Coherent X-Ray Diffraction

Abstract

We present a coherent x-ray diffraction study of the antiferrodistortive displacive transition of SrTiO{sub 3}, a prototypical example of a phase transition for which the critical fluctuations exhibit two length scales and two time scales. From the microbeam x-ray coherent diffraction patterns, we show that the broad (short-length scale) and the narrow (long-length scale) components can be spatially disentangled, due to 100-{mu}m-scale spatial variations of the latter. Moreover, both components exhibit a speckle pattern, which is static on a {approx}10 mn time scale. This gives evidence that the narrow component corresponds to static ordered domains. We interpret the speckles in the broad component as due to a very slow dynamical process, corresponding to the well-known central peak seen in inelastic neutron scattering.

Authors:
 [1];  [2];  [3]; ;  [4];  [5]
  1. Synchrotron SOLEIL, L'Orme des merisiers, Saint-Aubin BP 48, 91192 Gif-sur-Yvette cedex (France)
  2. Laboratoire de physique des solides, Universite Paris-sud, CNRS, UMR 8502, F-91405 Orsay Cedex (France)
  3. Institut Laue-Langevin, 6, rue Jules Horowitz, Boite postale 156, 38042 Grenoble Cedex 9 (France)
  4. European Synchrotron Radiation Facility, 6 rue Jules Horowitz, Boite postale 220, 38043 Grenoble Cedex (France)
  5. Laboratoire Structures, Proprietes et Modelisation des Solides, Ecole Centrale Paris, CNRS, UMR 8580, Grande Voie des Vignes, F-92295 Chatenay-Malabry Cedex (France)
Publication Date:
OSTI Identifier:
20957729
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 10; Other Information: DOI: 10.1103/PhysRevLett.98.105501; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; INELASTIC SCATTERING; NEUTRON DIFFRACTION; NEUTRON REACTIONS; PHASE TRANSFORMATIONS; STRONTIUM TITANATES; X-RAY DIFFRACTION

Citation Formats

Ravy, S., Bolloc'h, D. Le, Currat, R., Fluerasu, A., Mocuta, C., and Dkhil, B. SrTiO{sub 3} Displacive Transition Revisited via Coherent X-Ray Diffraction. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.105501.
Ravy, S., Bolloc'h, D. Le, Currat, R., Fluerasu, A., Mocuta, C., & Dkhil, B. SrTiO{sub 3} Displacive Transition Revisited via Coherent X-Ray Diffraction. United States. doi:10.1103/PHYSREVLETT.98.105501.
Ravy, S., Bolloc'h, D. Le, Currat, R., Fluerasu, A., Mocuta, C., and Dkhil, B. Fri . "SrTiO{sub 3} Displacive Transition Revisited via Coherent X-Ray Diffraction". United States. doi:10.1103/PHYSREVLETT.98.105501.
@article{osti_20957729,
title = {SrTiO{sub 3} Displacive Transition Revisited via Coherent X-Ray Diffraction},
author = {Ravy, S. and Bolloc'h, D. Le and Currat, R. and Fluerasu, A. and Mocuta, C. and Dkhil, B.},
abstractNote = {We present a coherent x-ray diffraction study of the antiferrodistortive displacive transition of SrTiO{sub 3}, a prototypical example of a phase transition for which the critical fluctuations exhibit two length scales and two time scales. From the microbeam x-ray coherent diffraction patterns, we show that the broad (short-length scale) and the narrow (long-length scale) components can be spatially disentangled, due to 100-{mu}m-scale spatial variations of the latter. Moreover, both components exhibit a speckle pattern, which is static on a {approx}10 mn time scale. This gives evidence that the narrow component corresponds to static ordered domains. We interpret the speckles in the broad component as due to a very slow dynamical process, corresponding to the well-known central peak seen in inelastic neutron scattering.},
doi = {10.1103/PHYSREVLETT.98.105501},
journal = {Physical Review Letters},
number = 10,
volume = 98,
place = {United States},
year = {Fri Mar 09 00:00:00 EST 2007},
month = {Fri Mar 09 00:00:00 EST 2007}
}
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