NEW COMPARISONS FOR LOCAL QUANTITIES OF THE TWO-DIMENSIONAL HUBBARD MODEL

ADOLFO AVELLA, FERDINANDO MANCINI
2003 International Journal of Modern Physics B  
We have compared the results of our approximation scheme, the composite operator method, for the double occupancy and the internal energy of the two-dimensional Hubbard model with numerical data obtained by means of the Lanczos and quantum Monte Carlo schemes. The agreement is very good at both half-filling and away from it showing how reliable is the approximation scheme.
doi:10.1142/s0217979203016224 fatcat:ay46txosiffmpcko2vfofnger4