Europhys. Lett.
Volume 63, Number 5, September 2003
Page(s) 674 - 680
Section General
Published online 01 November 2003
DOI: 10.1209/epl/i2003-00583-2
Europhys. Lett., 63 (5) , pp. 674-680 (2003)

Tailoring symmetry groups using external alternate fields

I. Junier and J. Kurchan

PMMH Ecole Supérieure de Physique et Chimie Industrielles 10 rue Vauquelin, 75231 Paris Cedex 05, France

(Received 9 April 2003; accepted in final form 25 June 2003)

Macroscopic systems with continuous symmetries subjected to oscillatory fields have phases and transitions that are qualitatively different from their equilibrium ones. Depending on the amplitude and frequency of the fields applied, Heisenberg ferromagnets can become XY or Ising-like -or, conversely, anisotropies can be compensated- thus changing the nature of the ordered phase and the topology of defects. The phenomenon can be viewed as an out-of-equilibrium form of order by disorder .

05.50.+q - Lattice theory and statistics (Ising, Potts, etc.).
75.40.Gb - Dynamic properties (dynamic susceptibility, spin waves, spin diffusion, dynamic scaling, etc.).

© EDP Sciences 2003