COERCIVITY MECHANISMS IN MODERN MAGNETIC MATERIALS

Abstract

  In this report the mechanisms of coercivity are briefly reviewed on the basis of micromagnetism. It is shown that the coercive field which depends on intrinsic as well as microstructural properties in general can be described by a universal relation H_c = (2K₁/M_s) α - N_eff M_s. The microstructural parameter α in particular is considered for volume and surface pinning in thin films. The minimum diameter of bit domains is shown to correspond to ∼ 4δ_B.