Quantum Heisenberg antiferromagnet in a field on the Tasaki square lattice
Abstract
Abstract We consider the S = 1/2 Heisenberg antiferromagnet on the Tasaki square lattice (flat-band spin system) and study its low-temperature thermodynamics around the saturation magnetic field. To this end, we construct a mapping of the ground states in the subspaces with total S z = N /2, …, N /3 ( N is the number of lattice sites) on the hard squares on an auxiliary square lattice and use classical Monte Carlo simulations to examine the latter classical system. The most prominent feature of the S = 1/2 Heisenberg antiferromagnet on the Tasaki square lattice under consideration is an order-disorder phase transition which occurs at a low temperature just below the saturation magnetic field and belongs to the 2D Ising universality class.
Fields of Study & Subjects
Theoretical and Computational Physics
Physics of Superconductivity and Magnetism
Advanced Condensed Matter Physics
Publication details
- Journal / source
- Zeitschrift für Naturforschung A
- Publisher
- Walter de Gruyter GmbH
- Volume
- 81
- Issue
- 5
- Pages
- 363–371
- Publication date
- 25 February 2026
- Language
- EN