A Three-Dimensional Computer Model of Domain Wall Motion in Magnetic Bubble Materials

The existing equations of motion for a domain wall, as initially proposed by Slonczewski, are modified to permit treatment of a curved wall, with associated magnetization structure,’ in three-dimensions. The equations are solved numerically, by the so-called explicit method, to investigate dynamic wall conversion in the case of a translating bubble. A comparatively large grid matrix of 3552 points is used to define a bubble of radius 3 µm. To reduce the otherwise enormous computation time required by such a matrix (a) the Dufort-Frankel scheme for the 2nd order spatial partial differentials was modified to permit a feasible time step, and (b) a combination of analytical and numerical methods in the demagnetizing and stray field calculation were employed. The principle of the numerical solution is given, and examples of bubble transport are included to illustrate the capability of the method.