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Self-adapting method for the localization of quantum critical points using Quantum Monte Carlo techniques

F. Alet·E. Sorensen
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Abstract

A generalization to the quantum case of a recently introduced algorithm (Y. Tomita and Y. Okabe, Phys. Rev. Lett. {\bf 86}, 572 (2001)) for the determination of the critical temperature of classical spin models is proposed. We describe a simple method to automatically locate critical points in (Quantum) Monte Carlo simulations. The algorithm assumes the existence of a finite correlation length in at least one of the two phases surrounding the quantum critical point. We illustrate these ideas on the example of the critical inter-chain coupling for which coupled antiferromagnetic S=1 spin chains order at T=0. Finite-size scaling relations are used to determine the exponents, $ν=0.72(2)$ and $η=0.038(3)$ in agreement with previous estimates.

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F. Alet, E. Sorensen. 2002-11-13. Self-adapting method for the localization of quantum critical points using Quantum Monte Carlo techniques. https://doi.org/10.1103/physrevb.65.092408

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