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Colossal Dielectric Constants in Braced Lattices with Defects

A. P. Ramirez·G. Lawes·V. Butko·M. A. Subramanian·C. M. Varma
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Abstract

The dielectric constant of CaCu3Ti4O12 is measured with a different electrode geometry than previous measurements. Similar colossal values are obtained showing that they are "intrinsic" to the material. We show that in braced structures such as CaCu3Ti4O12, a small concentration O(10-3) of defects, which disrupt the bracing and relax between different equivalent configurations, can lead to colossal dielectric constants above a characteristic temperature. The dielectric constant e(w,T) has a frequency and temperature dependence of the same form as found experimentally.

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A. P. Ramirez, G. Lawes, V. Butko, M. A. Subramanian, C. M. Varma. 2002-09-20. Colossal Dielectric Constants in Braced Lattices with Defects. https://arxiv.org/abs/cond-mat/0209498

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