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arXiv · cond-mat/9905247

Auxiliary-field Monte Carlo for Quantum Spin and Boson Systems

M. Ulmke·R. T. Scalettar
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Abstract

We describe a new algorithm for the numerical simulation of quantum spin and boson systems. The method is based on the Trotter decomposition in imaginary time and a decoupling by auxiliary Ising spins. It can be applied, in principle, to arbitrary (random) spin systems, however in general it suffers from the ``minus-sign problem''. This problem is absent in the case of the Ising model in a transverse field in arbitrary dimensions and geometries. We show test results for the spin--1/2 XY model, the one--dimensional transverse Ising model with disorder, and the phase transition induced by a transverse field in the two-dimensional Ising model.

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M. Ulmke, R. T. Scalettar. 1999-05-18. Auxiliary-field Monte Carlo for Quantum Spin and Boson Systems. https://doi.org/10.1103/physrevb.61.9607

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