Crossover from random-exchange to random-field critical behavior in Ising models

Article

关键词: CONCENTRATION-DEPENDENCE;    RENORMALIZATION-GROUP;    DISORDERED-SYSTEMS;    ANTIFERROMAGNETS;    SUMMABILITY;    FEXZN1-XF2;    EXPANSION;    6-LOOP;   

DOI  :  10.1103/PhysRevB.68.092409

来源: SCIE

【 摘 要 】

We compute the crossover exponent phi describing the crossover from the random-exchange to the random-field critical behavior in Ising systems. For this purpose, we consider the field-theoretical approach based on the replica method, and perform a six-loop calculation in the framework of a fixed-dimension expansion. The crossover from random-exchange to random-field critical behavior has been observed in dilute anisotropic antiferromagnets, such as FexZn1-xF2 and MnxZn1-xF2, when applying an external magnetic field. Our result phi=1.42(2) for the crossover exponent is in good agreement with the available experimental estimates.

【 授权许可】

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