2000/01/11 by D. Loison, K. D. Schotte · 29 citations
Mathematics · Physics and Astronomy · #Antiferromagnetism #Condensed matter physics #Heisenberg model #Hexagonal lattice #Mathematical physics #Mathematics #Monte Carlo method #Physics #Physics of Superconductivity and Magnetism #Quantum many-body systems #Quantum mechanics #Renormalization group #Spins #Statistical physics #Theoretical and Computational Physics #Universality (dynamical systems) #cond-mat.stat-mech
paper · pdf · doi:10.1007/s100510050113
published in The European Physical Journal B 14(1), 125-137 (Springer Science+Business Media) · 31 pages, 13 figures, to be published in Euro. J. Phys. B
arxiv created 2000/01/11 · openalex publication_date 2000/02/01 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Starting from the hypothesis of a second order transition we have studied modifications of the original Heisenberg antiferromagnet on a stacked triangular lattice (STA-model) by the Monte Carlo technique. The change is a local constraint restricting the spins at the corners of selected triangles to add up to zero without stopping them from moving freely (STAR-model). We have studied also the closely related dihedral and trihedral models which can be classified as Stiefel models. We have found indications of a first order transition for all three modified models instead of a universal critical behavior. This is in accordance with the renormalization group investigations but disagrees with the Monte Carlo simulations of the original STA-model favoring a new universality class. For the corresponding x-y antiferromagnet studied before, the second order nature of the transition could also not be confirmed.