arXiv subjects

Takeo Yamamoto

Publications and source records attributed to Takeo Yamamoto.

3 recordsLinked to original sources

arXiv2004

Finite spin-glass transition of the $\pm J$ XY model in three dimensions

A three-dimensional $\pm J$ XY spin-glass model is investigated by a nonequilibrium relaxation method. We have introduced a new criterion for the finite-time scaling analysis. A transition temperature is obtained by a crossing point of obtained data. The scaling analysis on the relaxation functions of the spin-glass susceptibility and the chiral-glass susceptibility shows that both transitions occur simultaneously. The result is checked by relaxation functions of the Binder parameters and the glass correlation lengths of the spin and the chirality. Every result is consistent if we consider that the transition is driven by the spin degrees of freedom.

cond-mat.dis-nn↗

arXiv2003

Weak universality of spin-glass transitions in three-dimensional $\pm J$ models

We find a possibility of a weak universality of spin-glass phase transitions in three-dimensional $\pm J$ models. The Ising, the XY and the Heisenberg models seem to undergo finite-temperature phase transitions with a ratio of the critical exponents $γ/ν\sim 2.4$. Evaluated critical exponents may explain corresponding experimental results. The analyses are based upon nonequilibrium relaxation from a paramagnetic state and finite-time scaling.

cond-mat.dis-nn↗

arXiv2003

Weak Universality of Spin Glasses in Three Dimensions

We point out a possibility of the weak universality of spin-glass phase transitions in three dimensions. The Ising, the XY, and the Heisenberg models with $\pm J$ bond distributions undergo finite-temperature phase transitions with a ratio of critical exponents $γ/ν=2.4$. Evaluated critical exponents agree with corresponding experimental results. The analyses are based upon the nonequilibrium relaxation from the paramagnetic state and the finite-time scaling.

cond-mat.dis-nn↗