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Raman studies of polycrystalline CaCu$_3$Ti$_4$O$_{12}$ under high-pressure

D. Valim·A. G. Souza Filho·P. T. C. Freire·A. P. Ayala·J. Mendes Filho·A. F. L. Almeida·P. B. A. Fechine·A. S. B. Sombra
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Abstract

We report a Raman scattering study of polycrystalline CaCu$_3$Ti$_4$O$_{12}$ (CCTO) under pressure up to 5.32 GPa. The pressure dependence of several Raman modes was investigated. No anomalies have been observed on the phonon spectra thereby indicating that the T$_{h}$ (Im$\bar 3$) structure remains stable for pressures up to 5.32 GPa. The pressure coefficients for the observed modes were determined. This set of parameters was used for evaluating the stress developed in CCTO thin films.

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D. Valim, A. G. Souza Filho, P. T. C. Freire, A. P. Ayala, J. Mendes Filho, A. F. L. Almeida, P. B. A. Fechine, A. S. B. Sombra. 2003-12-17. Raman studies of polycrystalline CaCu$_3$Ti$_4$O$_{12}$ under high-pressure. https://arxiv.org/abs/cond-mat/0312448

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