DOMAIN-WALL STRUCTURE IN BULK MAGNETIC MATERIAL

[摘要] A cross section of a wall in 10 mum thick material with Permalloy characteristics has been simulated on the massively parallel Thinking Machine system CM2 using direct integration of the LLG equation. A Cartesian lattice of 256 nodes representing 20 mum normal to the wall and 128 nodes in thickness was used. The expected stray-field-free structure was found with a vortex that extends nearly 10 mum from the Bloch wall center. The Bloch wall itself was well formed over 80% of the thickness with two thin Neel-like surface walls of opposite chirality. The Neel caps were wide and very asymmetric. If a width definition of 10%-10% of the wall normal magnetization is used, the width is 8.3 mum. The vortex is large and only on one side of the wall extending 10 mum to the edge of the simulation with as much as 10-degrees tilt of the magnetization away from the easy axis. The width of the Bloch wall in the sample center was 15% smaller than that predicted by the classic wall width.

[发布日期] 1994-05-01