Journal of Physics C Solid State Physics

Thermodynamics of six-vertex models in direct and staggered electric fields in the cluster approximation

Валентин Григорьевич Вакс, В. И. Зиненко

Published Jun 20, 1986• 6 citations

Abstract

The thermodynamics of the six-vertex models in direct and staggered electric fields is investigated using the cluster field method. The scheme of the successive approximations of the method is described and the result of the first and second approximations are presented. The cluster field method is shown to combine simplicity with high accuracy, in particular, in the description of ferroelectric phase transitions where the basic results agree with the exact ones in all the exactly soluble cases. The properties of the models in the staggered field s not=0 are investigated in detail. The expressions obtained for the ferroelectric phase transition point T F (s) and for the polarisability near T F (s) are apparently exact for the six-vertex models.

DOI: 10.1088/0022-3719/19/17/007

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