Computer simulation of vertical Bloch line propagation around stripe domain head

Vertical Bloch line pair propagation at the stripe domain head is studied by computer simulation. Several numerical techniques in the calculation are adopted to save computation time. The time step and the grid points interval are varied through the iterative computation. The side wall of the stripe domain is assumed to be straight to simulate a long domain with small number of grid points. Simulation results reveal that a thickness step inside the stripe domain is effective to control the wall motion. A half of the film thickness is chosen for the step depth. The VBL pairs at the stripe head can be propagated one bit period by applying a collapse bias pulse.