Abstract
Recent experiments demonstrate that at the Curie temperature the specific heat may be a smooth function of the temperature. We propose that this effect can be due to random impurities and substantiate our proposal by a study of an Ising model containing such impurities. We modify the usual rectangular lattice by allowing each row of vertical bonds to vary randomly from row to row with a prescribed probability function. In the case that this probability is a particular distribution with a narrow width, we find that the logarithmic singularity of Onsager's lattice is smoothed out into a function which at is infinitely differentiable but not analytic. This function is expressible in terms of an integral involving Bessel functions and is computed numerically.
- Received 9 July 1968
DOI:https://doi.org/10.1103/PhysRev.176.631
©1968 American Physical Society