Effective Field Methods for Magnetic Systems

• Authors: G. Kamieniarz , R. Dekeyser , G. Musiał
• Languages of publication: EN

Abstracts

EN

The self-consistency conditions inherent in the mean-field approximation are extended to take into account some pair correlations. Ii is shown that this extension is systematically improvable and applicable to the spin systems with short-range interactions in the entire temperature region. With two correlations included and the renormalization-group ideas implemented, the critical properties of the Ising model are satisfactorily revealed. Moreover, the improved estimates of the thermodynamical quantities for the quantum linear XY model from the finite-size calculations are found down to very low temperatures.

Keywords

EN

64.60.Cn; 64.60.Fr; 05.50.+q; 75.10.Dg; 75.10.Hk; 75.10.Jm; 75.40.Cx; 75.40.Mg

Discipline

• 75.40.Mg: Numerical simulation studies
• 75.10.Hk: Classical spin models
• 75.40.Cx: Static properties (order parameter, static susceptibility, heat capacities, critical exponents, etc.)
• 75.10.Dg: Crystal-field theory and spin Hamiltonians(see also 71.70.Ch Crystal and ligand fields)
• 05.50.+q: Lattice theory and statistics (Ising, Potts, etc.)(see also 64.60.Cn Order-disorder transformations, and 75.10.Hk Classical spin models)
• 75.10.Jm: Quantized spin models, including quantum spin frustration
• 64.60.Cn: Order-disorder transformations(see also 81.30.Hd Constant-composition solid-solid phase transformations: polymorphic, massive, and order-disorder in materials science; for effects of disorder on superconducting transition temperature, see 74.62.En)

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 1994
• Volume: 85
• Issue: 2
• Pages: 413-417

Dates

published

1994-02

Contributors

author

G. Kamieniarz

• Institute of Theoretical Physics, KU Leuven, Belgium

author

R. Dekeyser

• Institute of Theoretical Physics, KU Leuven, Belgium

author

G. Musiał

• Institute of Physics, A. Mickiewicz University, Matejki 48/49, 60-769 Poznań, Poland

Identifiers

DOI

10.12693/APhysPolA.85.413