** Next:** Introduction

# Lifetime of vortices in 2D easy-plane ferromagnets

**
D. A. Dimitrov
and
G. M. Wysin **

Department of Physics, Kansas State University,
Manhattan, KS 66506-2601

**Fri Sep 1 16:26:56 CDT 1995
**

### Abstract:

*
We use a combination of classical Monte Carlo and spin dynamics
simulations for the 2D classical easy-plane ferromagnet to
estimate the lifetime of free vortices near the
Kosterlitz-Thouless transition temperature.
Using thermal equilibrium initial states from Monte Carlo, the spin equations of
motion are integrated numerically and the number fluctuations of free vortices
are used to calculate the lifetime.
The inverse lifetime gives an estimate for a cutoff frequency
below which an ideal gas description of vortex dynamics is inappropriate.
For this reason we compare the lifetime results with simulations and
ideal gas phenomenology for
the dynamic structure function,
.
**
*

PACS numbers: 75.10.Hk, 75.30.Ds, 75.40.Gb, 75.40.Mg

Submitted to
Physical Review Letters

This preprint also available in RevTeX. (A zipped file including postscript figures).

*Gary M Wysin *

Fri Sep 1 16:26:33 CDT 1995