One of the most important of Ising models of disorder occurs when a random field is imposed which couples directly to the order parameter of the system. Unlike the pure d=3 Ising model, there is poor agreement between theory and simulations on the one hand and experiments on the other. This gave motivation to measure the critical behavior of the staggered magnetization, since this is one of the most valuable yet also least characterized aspects of the experimental system. The result for the order parameter exponent β provides an important quantitative experimental contribution toward a comprehensive understanding of the random-field Ising model (RFIM).
|Original language||English (US)|
|Journal||Physical review letters|
|State||Published - Oct 7 2002|
Bibliographical noteFunding Information:
We thank M. Matsuda, S. Katano, H. Yoshizawa, and J. A. Fernandez-Baca for allowing the use of unpublished neutron scattering results in the analysis shown in Fig. 1, and the SSRL staff for their help in building the magnet facility. The x-ray experiments were carried out at the Stanford Synchrotron Radiation Laboratory, a national user facility operated by Stanford University on behalf of the U.S. Department of Energy, Office of Basic Energy Sciences. The work at Stanford was also supported by the U.S. Department of Energy under Contracts No. DE-FG03-99ER45773 and No. DE-AC03-76SF00515, by NSF Grants No. DMR-9985067 and No. DMR-9802737, and by the A. P. Sloan Foundation. The work at UCSC was supported by the Department of Energy Grant No. DE-FG03-87ER45324. The work at West Virginia University was supported by NSF Grant No. DMR-9734051.