Magnetic Structures of an Iron–Gadolinium Multilayer at Low Temperatures

Low-temperature magnetic structures of an [Fe/Gd] 15 multilayer are determined using the resonant X-ray magnetic scattering technique at a synchrotron source. The difference intensities of specular Bragg reflections observed by flipping the helicity of circularly polarized probing X-rays of energy close to the L 3 absorption edge of Gd show that the multilayer is in the Gd-aligned state with the magnetic moments of the Gd layers oriented parallel to the applied in-plane field at H =0.5 kOe, T =10 K. This transforms into the twisted state with canted Gd moments by raising field strength H and/or temperature T . In the twisted state, the Gd moments at the interfaces and the core of the Gd layers show distinctive canting angles. Temperature and field-dependent in-plane rotations of local Gd moments have been visualized.