Observation of antiferromagnetic domains in nickel oxide by neutron diffraction topography

摘要

The antiferromagneticThyphen;domain structure of a singlehyphen;crystal plate of NiO was investigated by neutron diffraction topography. Two modes of observation were used. Topographs made using nuclear reflections provide images of the domain walls because of the change in lattice distortion associated with the antiferromagnetic ordering via exchange striction; the (non)visibility of walls depends on the Bragg reflection used, and is in good agreement with calculations. On topographs made using magnetic reflections, only one type of domain is imaged at a time, yielding unambiguous identification of the magnetic arrangement in each domain.