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Materials with Colossal Dielectric Constant: Do They Exist?

P. Lunkenheimer·V. Bobnar·A. V. Pronin·A. I. Ritus·A. A. Volkov·A. Loidl
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Abstract

Experimental evidence is provided that colossal dielectric constants, epsilon >= 1000, sometimes reported to exist in a broad temperature range, can often be explained by Maxwell-Wagner type contributions of depletion layers at the interface between sample and contacts, or at grain boundaries. We demonstrate this on a variety of different materials. We speculate that the largest intrinsic dielectric constant observed so far in non-ferroelectric materials is of order 100.

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P. Lunkenheimer, V. Bobnar, A. V. Pronin, A. I. Ritus, A. A. Volkov, A. Loidl. 2002-01-10. Materials with Colossal Dielectric Constant: Do They Exist?. https://doi.org/10.1103/physrevb.66.052105

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