Twisted domain wall structure for stripe domains in bubble films

A four-parameter variational model is used to calculate the properties of stripe domains in uniaxial magnetic films. The width of the stripes and the thickness of the walls between the stripes are allowed to vary. In addition, the effects of the demagnetizing fields across the walls are included by allowing the spins within the walls to twist out of the wall plane. It is shown that the presence of neighboring walls in this model yields a substantially higher wall energy density in most cases of importance to bubble technology than was previously reported by Schlömann for a similar model of an isolated wall, the stripe wall energy density being over 50 percent higher in the case where the dimensionless anisotropy parameter
q = K_{u}/2\piM^{2}
is 1.1 and the film thickness to material length ratio
h/l
is 9. A critical discussion of the significance of wall energies in such models is given, and a method is discussed by which the stripe-width information from this model may be used in interpreting stripe-width data to obtain material parameters to an accuracy hitherto unavailable.