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arXiv · 0909.5660

Theory of quantum paraelectrics and the metaelectric transition

G. J. Conduit·B. D. Simons
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Abstract

We present a microscopic model of the quantum paraelectric-ferroelectric phase transition with a focus on the influence of coupled fluctuating phonon modes. These may drive the continuous phase transition first order through a metaelectric transition and furthermore stimulate the emergence of a textured phase that preempts the transition. We discuss two further consequences of fluctuations, firstly for the heat capacity, and secondly we show that the inverse paraelectric susceptibility displays T^2 quantum critical behavior, and can also adopt a characteristic minimum with temperature. Finally, we discuss the observable consequences of our results.

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G. J. Conduit, B. D. Simons. 2009-09-30. Theory of quantum paraelectrics and the metaelectric transition. https://doi.org/10.1103/physrevb.81.024102

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