Spin glass transition as a problem of percolation of overlapping spheres

Abstract

A theory of substitutional as well as amorphous RKKY-type spin glasses has been developed following a qualitative idea first suggested by Smith and more recently by Mydosh. The theory has been developed to a stage where quantitative calculations become possible on realistic systems. The paramagnetic to spin-glass transition has been described as a percolation of temperature dependent clusters of spins in a continuum. The glass transition temperature has been obtained as a function of the magnetic impurity concentration, after taking the effects of frustration and finite mean free path into account. Different 'critical' temperatures for different experimental probes with characteristic time and length scales have also been studied.