Calculation of intrinsic coercivity of magnetic domain walls in perfect crystals

Abstract

The critical field strength at which a classical domain wall moves through a perfect ferromagnetic crystal of simplified structure is calculated as a function of the ratio between anisotropy energyKand ferromagnetic coupling energyC, taking into account the discrete nature of the spins. WhenKapproachesCintrinsic wall pinning becomes appreciable with critical fields approaching the anisotropy field whenK \\gg C. ForK/C \\geq 2/3, the wall has a thickness of one atomic distance and thus resembles a ferroelectric wall.