Magnetic Domain Walls in Single-Phase and Phase-Separated Double Exchange Systems

Abstract

We investigate the structure of magnetic domain walls in a classical double exchange ferromagnet, evaluating domain wall energies and charges. Three different cases are studied: (i) a conventional smooth Bloch wall, (ii) an abrupt Ising-type wall, which is shown to have lower energy at small values of carrier concentration, and (iii) stripe wall, corresponding to the two ferromagnetic domains being separated by a stripe of another, antiferromagnetic, phase. General aspects of energy balance and geometry of phase-separated states are discussed in this context. It is speculated that domain walls of the latter type may be responsible for the unusual transport properties of certain manganate films.