A generalization of Handscomb's quantum Monte Carlo scheme-application to the 1D Hubbard model

Abstract

A recently introduced generalization of Handscomb's quantum Monte Carlo scheme (1962) is further developed. Expressions for expectation values of various observables are studied in detail. A more efficient algorithm for importance sampling in a space of state vectors and operator strings is constructed, using the 1D Hubbard model as an illustrative example. As a test of the method, 32-site rings at band fillings 1/4, 3/8 and 1/2 are studied at a low temperature. Results for spin- and charge-density structure factors and static susceptibilities are presented.