On a Proposal for Determining the Thickness of the Transition Layer between Ferromagnetic Domains by a Neutron Polarization Experiment

Abstract

The surface energy of the Bloch wall between ferromagnetic domains is of fundamental importance in domain theory; this energy can be computed if the wall thickness is known. It is proposed that the wall thickness be measured by studying the polarization changes of a neutron beam which is passed through a single Bloch wall. The relation connecting wall thickness, neutron velocity, and polarization change is worked out; the required velocities are such that the experiment can probably be done with existing techniques, if grazing angles of incidence are used.