Barkhausen noise in the random field Ising magnetNd2Fe14B

Barkhausen noise in the random field Ising magnet Nd2Fe14B

J. Xu,1 D. M. Silevitch,1 K. A. Dahmen,2 and T. F. Rosenbaum1,3,* 1The James Franck Institute and Department of Physics, The University of Chicago, Chicago, Illinois 60637, USA 2Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA 3Division of Physics, Mathematics, and Astronomy, California Institute of Technology, Pasadena, California 91125, USA (Recei...

Random Field Ising Model

This paper gives an introduction to the Random Field Ising Model (RFIM). Since its rst discussion in the paper by Imry and Ma 1] there has been great interest in this model, since Ising or Ising-like systems in random elds are a good representation of a large number of impure materials. These show features that can not be understood by studying ideal systems (i.e. Ising model). There are a lot ...

Chaos in the random field Ising model

The sensitivity of the random field Ising model to small random perturbations of the quenched disorder is studied via exact ground states obtained with a maximum-flow algorithm. In one and two space dimensions we find a mild form of chaos, meaning that the overlap of the old, unperturbed ground state and the new one is smaller than 1, but extensive. In three dimensions the rearrangements are ma...

Theory of the Random Field Ising Model

A review is given on some recent developments in the theory of the Ising model in a random field. This model is a good representation of a large number of impure materials. After a short repetition of earlier arguments, which prove the absence of ferromagnetic order in d ≤ 2 space dimensions for uncorrelated random fields, we consider different random field correlations and in particular the ge...

Hysteresis, Avalanches, and Barkhausen Noise