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arXiv · 0811.1626

Ground-State Properties of a Heisenberg Spin Glass Model with a Hybrid Genetic Algorithm

Yuh-ichi Iyama·Fumitaka Matsubara
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Abstract

We developed a genetic algorithm (GA) in the Heisenberg model that combines a triadic crossover and a parameter-free genetic algorithm. Using the algorithm, we examined the ground-state stiffness of the $\pm J$ Heisenberg model in three dimensions up to a moderate size range. Results showed the stiffness constant of $θ= 0$ in the periodic-antiperiodic boundary condition method and that of $θ\sim 0.62$ in the open-boundary-twist method. We considered the origin of the difference in $θ$ between the two methods and suggested that both results show the same thing: the ground state of the open system is stable against a weak perturbation.

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Yuh-ichi Iyama, Fumitaka Matsubara. 2008-11-11. Ground-State Properties of a Heisenberg Spin Glass Model with a Hybrid Genetic Algorithm. https://doi.org/10.1143/jpsj.78.014703

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