Longwavelength anomalous diffusion mode in the twodimensional XY dipole magnet
Abstract
In a twodimensional XY ferromagnet the dipole force induces a strong interaction between spin waves in the longwavelength limit. The major effect of this interaction is the transformation of a propagating spin wave into a diffusion mode. We study the anomalous dynamics of such diffusion modes. We find that the JanssenDe Dominics functional, which governs this dynamics, approaches the nonGaussian fixed point. A spin wave propagates by an anomalous anisotropic diffusion with the dispersion relation: iω~k^{Δy}_{y} and iω~k^{Δx}_{x}, where Δ_{y}=47/27 and Δ_{x}=47/36. The lowfrequency response to the external magnetic field is found.
 Publication:

Physical Review B
 Pub Date:
 August 1997
 DOI:
 10.1103/PhysRevB.56.3181
 arXiv:
 arXiv:condmat/9607168
 Bibcode:
 1997PhRvB..56.3181A
 Keywords:

 75.30.Ds;
 68.35.Rh;
 68.45.Kg;
 68.60.p;
 Spin waves;
 Phase transitions and critical phenomena;
 Physical properties of thin films nonelectronic;
 Condensed Matter
 EPrint:
 34 pages, RevTeX, 2 .ps figures, the third figure is available upon request