Quantum discrete $ϕ^4$ model at finite temperatures: the mean-field phase diagram

V. V. Savkin; A. N. Rubtsov

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Quantum discrete $ϕ^4$ model at finite temperatures: the mean-field phase diagram

V. V. Savkin·A. N. Rubtsov

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Abstract

The quantum discrete $ϕ^4$ model at finite temperature is studied in the mean-field approximation. The phase diagrams are obtained for a wide range of the model parameters. The domains of applicability for the classical, quantum, and order-disorder limits are determined. It is shown that a remarkable part of the phase diagram is reproduced by the first quantum correction to the classical result. Parameters of Sn$_2$P$_2$S$_6$, SrTiO$_3$, and KH$_2$PO$_4$ are placed in the phase diagram of the model.

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BibTeX RIS

V. V. Savkin, A. N. Rubtsov. 2002-01-27. Quantum discrete $ϕ^4$ model at finite temperatures: the mean-field phase diagram. https://arxiv.org/abs/cond-mat/0112429

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