Physics – Condensed Matter – Statistical Mechanics
Scientific paper
1998-04-03
Phys.Rev. B53 (1996) 11593-11605
Physics
Condensed Matter
Statistical Mechanics
14 pages, 5 figures
Scientific paper
10.1103/PhysRevB.53.11593
The self-consistent Gaussian approximation (SCGA) for classical spin systems described by a completely anisotropic D-component vector model is proposed, which takes into account fluctuations of the molecular field and thus is a next step beyond the molecular field approximation. The SCGA is sensitive to the lattice dimension and structure and to the form of spin interactions and yields rather accurate values of the field-dependent magnetization m(H,T) and other thermodynamic functions in the whole plane (H,T) excluding the vicinity of the critical point (0,T_c), where the SCGA breaks down, showing a first-order phase transition. The values of T_c themselves can be determined in the SCGA with an accuracy better than 1% for actual 3-dimensional structures. At low and high temperatures the SCGA recovers the leading terms of the spin-wave theory, the low- and high-temperature series expansions, respectively. The accuracy of the SCGA increases with the increase of the spin dimension D, and in the limit D \to \infty the exact solution for the spherical model is recovered.
No associations
LandOfFree
Self-Consistent Gaussian Approximation for Classical Spin Systems: Thermodynamics does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Self-Consistent Gaussian Approximation for Classical Spin Systems: Thermodynamics, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Self-Consistent Gaussian Approximation for Classical Spin Systems: Thermodynamics will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-348376