Quantum Monte Carlo study of the half-filled Hubbard model on the honeycomb lattice

24th IUPAP Conference on Computational Physics

物理学;计算机科学

Otsuka, Yuichi^1 ; Yunoki, Seiji^1,2,3 ; Sorella, Sandro^1,4,5

Computational Materials Science Research Team, RIKEN AICS, Hyogo 650-0047, Kobe, Japan^1

Computational Condensed Matter Physics Laboratory, RIKEN ASI, Saitama 351-0198, Japan^2

CREST, Japan Science and Technology, Kawaguchi, Saitama 332-0012, Japan^3

SISSA-International School for Advanced Studies, Via Bonomea 265, 34136 Trieste, Italy^4

Democritos Simulation Center, CNR-IOM Instituto Officina Dei Materiali, 34151 Trieste, Italy^5

关键词: Finite size scaling;    High degree of accuracy;    Honeycomb lattices;    Hubbard interaction;    Nearest neighbor hopping;    Quantum Monte Carlo simulations;    Quantum monte carlo studies;    Spin-spin correlation functions;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/454/1/012045/pdf
DOI  :  10.1088/1742-6596/454/1/012045

学科分类：计算机科学（综合）

来源: IOP

【 摘 要 】

The half-filled Hubbard model on the honeycomb lattice is investigated by numerically exact large-scale quantum Monte Carlo simulations for lattice sizes up to 2592 sites. By performing careful finite-size scaling for the spin-spin correlation functions, calculated with a high degree of accuracy, we find that the ground state is antiferromagnetically long-range ordered at U/t 4, where U is the on-site Hubbard interaction and t is the nearest neighbor hopping. Our result is in sharp contrast to a recent report [Meng et al., Nature 464, 847 (2010)], where instead strong evidence of spin liquid behavior is found.