1998/06/25 by F. F. Assaad, Assaad, F. F. · 2 citations
Physics and Astronomy · #FOS: Physical sciences #Magnetic properties of thin films #Physics of Superconductivity and Magnetism #Strongly Correlated Electrons (cond-mat.str-el) #Theoretical and Computational Physics #cond-mat.str-el
paper · pdf · doi:10.48550/arxiv.cond-mat/9806307
5 pages including 2 figures in encapsulated postscript format
arxiv created 1998/06/25 · openalex publication_date 1998/06/25 · arxiv updated 2009/11/30 · openalex created_date 2022/10/22 · openalex updated_date 2026/07/28
Auxiliary field quantum Monte Carlo methods for Hubbard models are generally based on a Hubbard-Stratonovitch transformation where the field couples to the z-component of the spin. This transformation breaks SU(2) spin invariance. The symmetry is restored only after summation over the auxiliary fields. Here, we analyze an alternative decomposition, which conserves SU(2) spin invariance, but requires the use of complex numbers. We show that this algorithm gets rid of the very large fluctuations observed in imaginary time displaced correlation functions of quantities which do not commute with the z-component of the total spin. The algorithm prooves to be efficient for the study of spin dynamics.