Monte Carlo study of superfluid-insulator transitions in Boson Hubbard models

Владимир Федорович Елесин, V. А. Kashurnikov, L. А. Openov

Federico Becca, Manuela Capello

Fabien Alet, Erik Schwartz Sørensen

Naomichi Hatano

Superfluid-insulator transitions are studied for the ground state of the Boson Hubbard model with random potentials. The topology of the phase diagram is discussed. Reentrant transitions between the superfluid phase and the Bose-glass insulator phase are found in an arbitrary number of dimensions. The present results are based on a perturbational scaling argument and a quantum Monte Carlo calculation. The Monte Carlo algorithm is also reported in detail.

H. Yokoyama, T. Miyagawa, Masao Ogata

Masahito Hashimoto, Masako Takasu

For some systems in critical phenomena, Monte Carlo (MC) simulations using conventional algorithm are inefficient, because of long correlation between successive MC configurations. Our system in Eq. (1) suffers this difficulty in critical region between superfluid phase and glass insulator phase. The loop algorithm overcomes this difficulty. We try to apply this algorithm to the soft core boson system, and carry out calculations with random boson Hubbard model.