Quantum Monte Carlo simulation of the one-dimensional periodic Anderson model - non-half-filled cases

T. Saso

Tetsuro Saso, Yutaka Seino

Quantum Monte Carlo[MC] calculation of one-dimensional periodic Anderson model without orbital degeneracy is performed by use of the path-integral formulation. Local f moment coincides well with the recent MC calculation for single impurity by Hirsch and Fye above the temperature at which antiferromagnetic correlation starts to grow, and decreases faster than those for single impurity and coupled two impurities below that temperature. Overall features, including susceptibilities, resemble one-dimensional Hubbard model with half-filled band.

Aleksander Zujev, Richard T. Scalettar, G. G. Batrouni +1 more

Studies of systems with two fermionic bands (or equivalently, layers) with repulsive interaction strength U have a long history, with the periodic Anderson model (PAM) being one of the most frequently considered Hamiltonians. In this paper, we use quantum Monte Carlo to study analogous issues for attractive interactions. As in the PAM, we focus on a case where one band (layer) is uncorrelated ( U = 0), and the effect of hybridization V between the bands (layers) on the pairing correlations. A key difference with the PAM is that there is no sign problem, so that we are better able to explore the physics of doped bilayer attractive systems at low temperatures (except in the case of exponentially small transition temperatures) whereas ground state properties of repulsive models can be determined only at half-filling. For small V , pairing in the U < 0 layer induces pairing in the U = 0 layer. At larger V superfluidity is suppressed at the low but finite T at which the quantum Monte Carlo was performed. The quantum Monte Carlo data are complemented by results obtained with the Bogoliubov–de Gennes approximation.

M. Gulácsi, Ian P. McCulloch

Shuxiang Yang, Juana Moreno, Mark Jarrell

Liu Chuan

Using the path integral representation, the Hubbard and the periodic Anderson model on D -dimensional cubic lattice are transformed into field theories of fermions in D + 1 dimensions. These theories at half-filling possess a positive definite real symmetry fermion matrix and can be simulated using the hybrid Monte Carlo method.