Nonlinear and spin-glass susceptibilities of three site-diluted systems

Article

关键词: CRITICAL EXPONENTS;    MONTE-CARLO;    CRITICAL-BEHAVIOR;    TEMPERATURES;   

DOI  :  10.1103/PhysRevB.84.104403

来源: SCIE

【 摘 要 】

The nonlinear magnetic chi(3) and spin-glass chi(SG) susceptibilities in zero applied field are obtained from tempered Monte Carlo simulations for three different spin glasses (SGs) of Ising spins with quenched site disorder. We find that the relation -T-3 chi(3) =. chi(SG) - 2/3 (T is the temperature), which holds for Edwards-Anderson SGs, is approximately fulfilled in canonical-like SGs. For nearest-neighbor antiferromagnetic interactions on a 0.4 fraction of all sites in face-centered cubic (fcc) lattices, as well as for spatially disordered Ising dipolar (DID) systems, -T-3 chi(3) and chi(SG) appear to diverge in the same manner at the critical temperature T-SG. However, -T-3 chi(3) is smaller than chi(SG) by over two orders of magnitude in the diluted fcc system. In DID systems, -T-3 chi(3)/chi(SG) is very sensitive to the system's aspect ratio. Whereas, near T-SG, chi(SG) varies by approximately a factor of 2 as system shape varies from cubic to long-thin-needle shapes, chi(3) sweeps over some four decades.

【 授权许可】

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