The magnetic properties of materials are fundamentally determined by their atomic structure and electronic configuration. In thin films and nanostructures, surface and interfacial effects can profoundly alter the magnetic behavior compared to the bulk material, leading to unique phenomena relevant for spintronics and magnetic recording. This article conceptually investigates the disparities between surface and bulk magnetization, with a particular emphasis on how magneto-optical techniques can effectively differentiate and characterize these distinct magnetic responses. We explore the principles of magneto-optical effects, such as the Kerr effect, which are inherently sensitive to the surface and near-surface magnetic moments. The proposed methodology involves utilizing these techniques to probe the magnetic hysteresis loops and reversal mechanisms at the surface, in comparison with bulk magnetic measurements (e.g., SQUID magnetometry). By examining the conceptual outcomes related to phenomena like exchange bias and training effects, we aim to elucidate how interfacial coupling can create asymmetry and shifts in the surface hysteresis, distinct from the underlying bulk. This comparative analysis provides critical insights into the microscopic origins of magnetism at interfaces, offering a powerful framework for designing advanced magnetic materials with tailored surface functionalities.

Interfacial magnetism, bulk magnetism, magneto-optical analysis

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