Phase diagram of the two-dimensional quantum antiferromagnet in a magnetic field
Year: 2006
Authors: Cuccoli A., Gori G., Vaia R., Verrucchi P.
Autors Affiliation: iv Florence, Dipartimento Fis, I-50019 Sesto Fiorentino, FI, Italy; INFM, Unita Ric Firenze, I-50019 Sesto Fiorentino, FI, Italy.
Abstract: The two-dimensional Heisenberg antiferromagnet experiences an effective easy-plane anisotropy when a magnetic field is applied, giving rise to Berezinskii-Kosterlitz-Thouless (BKT) critical behavior. Remarkably, the strength of the effective anisotropy, and consequently the critical BKT temperature, can be tuned by varying the field. By means of the pure-quantum self-consistent harmonic approximation, that reduces the quantum model to an effective classical system, the phase diagram is constructed from its known classical counterpart. By classical Monte Carlo simulations of the effective system the thermodynamic quantities can be calculated. Comparison is made with the behavior observed experimentally in the S=5/2 compound Mn(HCOO)(2)2H(2)O. (C) 2006 American Institute of Physics.
Journal/Review: JOURNAL OF APPLIED PHYSICS
Volume: 99 (8) Pages from: 08H503-1 to: 08H503-3
KeyWords: Heisenberg-antiferromagnet; Anti-ferromagnet; Square-lattice; Thermodynamics; Mn(hcoo)2.2h2oDOI: 10.1063/1.2172209Citations: 10data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2025-09-14References taken from IsiWeb of Knowledge: (subscribers only)
