Temperature dependent magnetic domain structure in ultrathin Fe films on Cr(100)

Magnetic microscopy is used to study the temperature dependent magnetization structures in 2 nm Fe films on Cr(100). Above the Cr Neel temperature, the Fe films can be magnetized into a single domain state. When the films are cooled below the Neel temperature the Fe magnetization has a tendency to turn perpendicular (in-plane) resulting in a spatially varying magnetization direction. The resulting magnetization structures are highly reproducible. The tendency of the Fe magnetization to rotate is attributed to frustration due to atomic steps. It is suggested that the local angle of magnetization rotation reflects the average step density. (C) 2000 American Institute of Physics. [S0021-8979(00)65608-6].