Two types of 180 degrees domain walls on a 115 nm cobalt film are obse
rved by magnetic force microscopy. The surface Neel wall on top of an
asymmetric Bloch wall is found inhomogeneous. with the width estimated
to be around 200 nm. The width of the rhomb-structured cross-tie wall
, on the other hand, is approximately 400 nm. The coexistence of these
two types of domain walls indicates that their wall energies are comp
arable at the film thickness. (C) 1998 American institute of Physics.