arXiv subjects

Shin-ichi Endoh

Publications and source records attributed to Shin-ichi Endoh.

3 recordsLinked to original sources

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↗

arXiv2001

Spin-Glass and Chiral-Glass Transitions in a $\pm J$ Heisenberg Spin-Glass Model in Three Dimensions

The three-dimensional $\pm J$ Heisenberg spin-glass model is investigated by the non-equilibrium relaxation method from the paramagnetic state. Finite-size effects in the non-equilibrium relaxation are analyzed, and the relaxation functions of the spin-glass susceptibility and the chiral-glass susceptibility in the infinite-size system are obtained. The finite-time scaling analysis gives the spin-glass transition at $T_{\rm sg}/J=0.21_{-0.02}^{+0.01}$ and the chiral-glass transition at $T_{\rm cg}/J=0.22_{-0.03}^{+0.01}$. The results suggest that both transitions occur simultaneously. The critical exponent of the spin-glass susceptibility is estimated as $γ_{\rm sg}= 1.7 \pm 0.3$, which makes an agreement with the experiments of the insulating and the canonical spin-glass materials.

cond-mat.dis-nn↗