2000/12/31 by P. M. Duxbury, J. H. Meinke
Physics and Astronomy · #cond-mat.dis-nn
paper · pdf · doi:10.1103/physreve.64.036112
published as Phys. Rev. E 64, 036112 (2001) · 4 pages 2 figures, corrected prefactors caused by a missing factor of two in Eq. 2., added a paragraph in conclusions for clarity
arxiv created 2001/01/16 · arxiv updated 2009/11/30
Two attractive and often used ideas, namely universality and the concept of a zero temperature fixed point, are violated in the infinite-range random-field Ising model. In the ground state we show that the exponents can depend continuously on the disorder and so are non-universal. However, we also show that at finite temperature the thermal order parameter exponent one half is restored so that temperature is a relevant variable. The broader implications of these results are discussed.