Computer simulation for wall merging process in Bloch line read operation

The behaviour of time-dependent micromagnetic structures during domain wall merging, which plays an important role in the read operation of the Bloch line memory, have been studied precisely by solving the Gilbert equation. The modified Dufort-Frankel scheme for the second-order spatial differential was used to obtain a practical time step. Simulation results indicated that the walls of an S=(1, 2, 0) stripe were merged more easily than those of an S=(1, 0, 0) stripe. It was found that wall merging begins near the film surfaces. When an in-plane magnetic field was applied along the walls in the S =(1, 0, 0) stripe, all merging occurred easily due to the change in wall structure caused by the generation of a horizontal Bloch line