High-temperature series for the bond-diluted Ising model in 3, 4, and 5 dimensions

Article

关键词: UPPER CRITICAL DIMENSION;    CRITICAL-BEHAVIOR;    CRITICAL EXPONENTS;    LOGARITHMIC CORRECTIONS;    EXPANSION APPROACH;    MONTE-CARLO;    POTTS;    FERROMAGNETS;    PERCOLATION;    IMPURITIES;   

DOI  :  10.1103/PhysRevB.74.144201

来源: SCIE

【 摘 要 】

In order to study the influence of quenched disorder on second-order phase transitions, high-temperature series expansions of the susceptibility and the free energy are obtained for the quenched bond-diluted Ising model in d=3-5 dimensions. They are analyzed using different extrapolation methods tailored to the expected singularity behaviors. In d=4 and 5 dimensions we confirm that the critical behavior is governed by the pure fixed point up to dilutions near the geometric bond percolation threshold. The existence and form of logarithmic corrections for the pure Ising model in d=4 are confirmed, and our results for the critical behavior of the diluted system are in agreement with the type of singularity predicted by renormalization group considerations. In three dimensions we find large crossover effects between the pure Ising, percolation, and random fixed points. We estimate the critical exponent of the susceptibility to be gamma=1.305(5) at the random fixed point.

【 授权许可】

Free