Simulations of Disordered Bosons on Hyper-Cubic Lattices

Peter Hitchcock; Erik S. Sorensen

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arXiv · cond-mat/0601180

Simulations of Disordered Bosons on Hyper-Cubic Lattices

Peter Hitchcock·Erik S. Sorensen

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Abstract

We address computational issues relevant to the study of disordered quantum mechanical systems at very low temperatures. As an example we consider the disordered Bose- Hubbard model in three dimensions directly at the Bose-glass to superfluid phase transition. The universal aspects of the critical behaviour are captured by a (3 + 1) dimensional link-current model for which an efficient 'worm' algorithm is known. We present a calculation of the distribution of the superfluid stiffness over the disorder realizations, outline a number of important considerations for performing such estimates, and suggest a modification of the link-current Hamiltonian that improves the numerical efficiency of the averaging procedure without changing the universal properties of the model.

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Peter Hitchcock, Erik S. Sorensen. 2006-01-10. Simulations of Disordered Bosons on Hyper-Cubic Lattices. https://arxiv.org/abs/cond-mat/0601180

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