Magnetism of 2d Heisenberg classical square lattices: theory vs experiments
Language
en
Article de revue
This item was published in
physica status solidi (c). 2014, vol. 11, n° 5-6, p. 989-994
Wiley
English Abstract
In this article, we exclusively focus on the low-temperature behaviors of 2d square lattices composed of (2N +1)2classical spins with isotropic couplings between first-nearest neighbors (Heisenberg couplings), in the ...Read more >
In this article, we exclusively focus on the low-temperature behaviors of 2d square lattices composed of (2N +1)2classical spins with isotropic couplings between first-nearest neighbors (Heisenberg couplings), in the thermodynamic limit (N →+∞). After briefly recalling the theoretical closed-form expressions derived for (i) the zero-field partition function ZN (0), (ii) the spin-spin correlation between any two lattice sites, (iii) the correlation length and (iv) the static susceptibility, we build up a diagram characterized by three low-temperature magnetic phases. Moreover we show that the behaviors of these physical quantities as well as the diagram are in perfect agreement with the corresponding ones derived using a renormalization method. Finally we give criterions allowing to directly determine the magnetic phases characterizing 2d magnetic compounds described by our microscopic model. An experimental test is given for illustrating this theoretical study. It allows one to obtain a perfect fit of the susceptibility of [{Mn(DENA)2(N3)2}n] (DENA is the ligand diethylnicotinamide).Read less <
English Keywords
spin lattices
Heisenberg model
antiferromagnetism
renormalization group
Origin
Hal imported