Analytical Description of the Critical Behavior of a Three-Dimensional Uniaxial Magnet in an External Field by Singling Out a Reference System

Authors

  • M. P. Kozlovskii Institute for Condensed Matter Physics, Nat. Acad. of Sci. of Ukraine
  • I. V. Pylyuk Institute for Condensed Matter Physics, Nat. Acad. of Sci. of Ukraine

DOI:

https://doi.org/10.15407/ujpe60.04.0362

Keywords:

Ising model, critical behavior, reference system, non-Gaussian distributions, free energy

Abstract

The critical behavior of systems belonging to the universality class of the three-dimensional Ising model has been studied theoretically. A three-dimensional Ising-like system with exponentially decreasing interaction potential and in the presence of a homogeneous external field was considered in the framework of the collective variables method. A specific feature in the calculation of the partition function and the free energy of a uniaxial magnet consists in singling out a reference system. The role of the latter is played by the molecular-field Hamiltonian. A method to describe the critical behavior with the use of a singled out reference system is developed on the basis of a non-Gaussian (quartic) distribution of order-parameter fluctuations (the p4 model).

Published

2019-01-19

How to Cite

Kozlovskii, M. P., & Pylyuk, I. V. (2019). Analytical Description of the Critical Behavior of a Three-Dimensional Uniaxial Magnet in an External Field by Singling Out a Reference System. Ukrainian Journal of Physics, 60(4), 362. https://doi.org/10.15407/ujpe60.04.0362

Issue

Section

General problems of theoretical physics