Magnetic Domains and Domain Walls: Understanding Ferromagnetic Structures

This lecture delves into the concept of magnetic domains and domain walls in ferromagnetic materials, exploring how they form due to the interplay of uniaxial anisotropy and demagnetizing fields. Through detailed illustrations and examples, the instructor explains the ideal domain configurations, closure domains, and the impact of sample thickness and anisotropy type on domain structures. The lecture also covers the formation of domains in saturated magnetic materials and their energy considerations, providing insights into the magnetostatic and wall energies involved. Additionally, the lecture showcases experimental techniques like X-ray magnetic circular dichroism to study domain structures in thin films.