Phase diagram and critical behavior of the square-lattice Ising model with competing nearest- and next-nearest-neighbor interactions

• Published in: arXiv.org
• Main Authors: Yin, Junqi, Landau, D P
• Format: Paper Journal Article
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 22.09.2009
• Subjects: Algorithms; Antiferromagnetism; Computer simulation; Data analysis; Ising model; Monte Carlo simulation; Phase diagrams; Physics - Computational Physics; Physics - Statistical Mechanics
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.0909.4000

Using the parallel tempering algorithm and GPU accelerated techniques, we have performed large-scale Monte Carlo simulations of the Ising model on a square lattice with antiferromagnetic (repulsive) nearest-neighbor(NN) and next-nearest-neighbor(NNN) interactions of the same strength and subject to a uniform magnetic field. Both transitions from the (2x1) and row-shifted (2x2) ordered phases to the paramagnetic phase are continuous. From our data analysis, reentrance behavior of the (2x1) critical line and a bicritical point which separates the two ordered phases at T=0 are confirmed. Based on the critical exponents we obtained along the phase boundary, Suzuki's weak universality seems to hold.