New Point of View on Metastability in Spin-Glasses

Abstract

It is shown that the Onsager theory, which distinguishes the Weiss field, the cavity field, and the reaction field, must be used in spin-glasses as the reaction field can be large. Along this line a simple mean-field theory permits one to recover results similar to those of Thouless, Anderson, and Palmer. Moreover the anisotropy of the reaction field explains the "two-level systems" introduced in these materials in order to explain the low-temperature properties such as hysteresis, remanence, etc.