7 research outputs found
Analysis of wasp-waisted hysteresis loops in magnetic rocks
The random-field Ising model of hysteresis is generalized to dilute magnets
and solved on a Bethe lattice. Exact expressions for the major and minor
hysteresis loops are obtained. In the strongly dilute limit the model provides
a simple and useful understanding of the shapes of hysteresis loops in magnetic
rock samples.Comment: 11 pages, 4 figure
Critical Hysteresis in Random Field XY and Heisenberg Models
We study zero-temperature hysteresis in random-field XY and Heisenberg models
in the zero-frequency limit of a cyclic driving field. We consider three
distributions of the random field and present exact solutions in the mean field
limit. The results show a strong effect of the form of disorder on critical
hysteresis as well as the shape of hysteresis loops. A discrepancy with an
earlier study based on the renormalization group is resolved.Comment: 10 pages, 6 figures; this is published version (added some text and
references
Hysteresis in Random Field XY and Heisenberg Models: Mean Field Theory and Simulations at Zero Temperature
We examine zero temperature hysteresis in random field XY and Heisenberg
models in the zero frequency limit of a cyclic driving field. Exact expressions
for hysteresis loops are obtained in the mean field approximation. These show
rather unusual features. We also perform simulations of the two models on a
simple cubic lattice and compare them with the predictions of the mean field
theory.Comment: replaced by the published versio