Equilibrium random-field Ising critical scattering in the antiferromagnet Fe(0.93)Zn(0.07)F2

TL;DR

This study demonstrates that equilibrium critical scattering in the random-field Ising model can be observed in dilute antiferromagnets like Fe(0.93)Zn(0.07)F2, enabling precise measurement of critical exponents and universal behavior.

Contribution

It shows that equilibrium RFIM critical scattering is feasible in dilute antiferromagnets, providing new insights into critical phenomena near phase transitions.

Findings

Critical exponents nu = 0.87 ± 0.07 and eta = 0.20 ± 0.05 measured

Universal scattering line shape extracted using scaling techniques

Amplitude ratios characterized for the RFIM system

Abstract

It has long been believed that equilibrium random-field Ising model (RFIM) critical scattering studies are not feasible in dilute antiferromagnets close to and below Tc(H) because of severe non-equilibrium effects. The high magnetic concentration Ising antiferromagnet Fe(0.93)Zn(0.07)F2, however, does provide equilibrium behavior. We have employed scaling techniques to extract the universal equilibrium scattering line shape, critical exponents nu = 0.87 +- 0.07 and eta = 0.20 +- 0.05, and amplitude ratios of this RFIM system.