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Quantum Monte Carlo Study of Random Antiferromagnetic Heisenberg Chain

Synge Todo·Kiyoshi Kato·Hajime Takayama
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Abstract

Effects of randomness on the spin-1/2 and 1 antiferromagnetic Heisenberg chains are studied using the quantum Monte Carlo method with the continuous-time loop algorithm. We precisely calculated the uniform susceptibility, string order parameter, spatial and temporal correlation length, and the dynamical exponent, and obtained a phase diagram. The generalization of the continuous-time loop algorithm for the systems with higher-S spins is also presented.

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Synge Todo, Kiyoshi Kato, Hajime Takayama. 1998-03-09. Quantum Monte Carlo Study of Random Antiferromagnetic Heisenberg Chain. https://arxiv.org/abs/cond-mat/9803088

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