Accession Number : ADA469784


Title :   Theory of Collective Spin-Wave Modes of Interacting Ferromagnetic Spheres


Descriptive Note : Journal article


Corporate Author : CALIFORNIA UNIV IRVINE DEPT OF PHYSICS AND ASTRONOMY


Personal Author(s) : Arias, Rodrigo ; Mills, D L


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a469784.pdf


Report Date : 29 Sep 2004


Pagination or Media Count : 8


Abstract : We formulate the theory of the collective spin wave modes of arrays of spherical particles of ferromagnetic material, under the assumption that each sphere in the array is magnetized uniformly. In addition, the intersphere interactions have their origin in the magnetic fields generated by the precessing moments, appropriate to the case where there is no direct physical contact between the spheres. The formulation is a real space analysis, and thus can be applied in principle to disordered arrangements of spheres. While our formulation is quite general, and is directly applicable to the case where both exchange and dipolar interactions influence spin motions within an individual sphere, explicit calculations are presented for the case where exchange is absent. The numerical calculations we discuss explore the collective spin wave modes of square planar arrays of spheres, and consider the case where the spheres are magnetized both perpendicular and parallel to the plane.


Descriptors :   *NUMERICAL ANALYSIS , *FERROMAGNETIC MATERIALS , *SPIN WAVES , REPRINTS , MAGNETIC DIPOLES , SPHERES , MAGNETIC FIELDS


Subject Categories : Properties of Metals and Alloys
      Theoretical Mathematics
      Operations Research
      Electricity and Magnetism


Distribution Statement : APPROVED FOR PUBLIC RELEASE