Antiferromagnetic Ising model in an imaginary magnetic field

Azcoiti, Vicente (Universidad de Zaragoza) ; Di Carlo, Giuseppe ; Follana, Eduardo (Universidad de Zaragoza) ; Royo-Amondarain, Eduardo (Universidad de Zaragoza)

Resumen: We study the two-dimensional antiferromagnetic Ising model with a purely imaginary magnetic field, which can be thought of as a toy model for the usual ¿ physics. Our motivation is to have a benchmark calculation in a system which suffers from a strong sign problem, so that our results can be used to test Monte Carlo methods developed to tackle such problems. We analyze here this model by means of analytical techniques, computing exactly the first eight cumulants of the expansion of the effective Hamiltonian in powers of the inverse temperature, and calculating physical observables for a large number of degrees of freedom with the help of standard multiprecision algorithms. We report accurate results for the free energy density, internal energy, standard and staggered magnetization, and the position and nature of the critical line, which confirm the mean-field qualitative picture, and which should be quantitatively reliable, at least in the high-temperature regime, including the entire critical line.

Idioma: Inglés

DOI: 10.1103/PhysRevE.96.032114

Año: 2017

Publicado en: Physical Review E 96, 3 (2017), 032114 [11 pp]
ISSN: 2470-0045

Factor impacto JCR: 2.284 (2017)

Categ. JCR: PHYSICS, MATHEMATICAL rank: 7 / 55 = 0.127 (2017) - Q1 - T1
Categ. JCR: PHYSICS, FLUIDS & PLASMAS rank: 12 / 31 = 0.387 (2017) - Q2 - T2

Factor impacto SCIMAGO: 0.979 - Condensed Matter Physics (Q1) - Statistical and Nonlinear Physics (Q1) - Statistics and Probability (Q2)

Financiación: info:eu-repo/grantAgreement/ES/DGA/E24-2
Financiación: info:eu-repo/grantAgreement/ES/MINECO/FPA2012-35453
Financiación: info:eu-repo/grantAgreement/ES/MINECO/FPA2015-65745-P

Tipo y forma: Artículo (Versión definitiva)

Área (Departamento): Área Física Teórica (Dpto. Física Teórica)