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Phase Transition of a Heisenberg Spin-Glass Model in Three Dimensions

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 نشر من قبل Takayuki Shirakura
 تاريخ النشر 2000
  مجال البحث فيزياء
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We study the phase transition of the $pm J$ Heisenberg model in three dimensions. Using a dynamical simulation method that removes a drift of the system, the existence of the spin-glass (SG) phase at low temperatures is suggested. The transition temperature is estimated to be $T_{rm SG} sim 0.18J$ from both equilibrium and off-equilibrium Monte-Carlo simulations. Our result contradicts the chirality mechanism of the phase transition reported recently by Kawamura which claims that it is not the spins but the chiralities of the spins that are ordered in Heisenberg SG systems.

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