How is Magnetic Anisotropy Enhanced at the Nanoscale?
Several methods are employed to enhance magnetic anisotropy at the nanoscale, including:
Shape Anisotropy: By designing nanoparticles with specific shapes (e.g., nanorods, nanodisks), the magnetic anisotropy can be tailored to desired directions. Surface Anisotropy: The surface-to-volume ratio increases significantly at the nanoscale, making surface effects more pronounced. Surface modifications, such as coating nanoparticles with different materials, can enhance anisotropy. Strain Engineering: By applying mechanical strain to nanomaterials, the crystal structure can be altered, thereby enhancing magnetic anisotropy. Exchange Bias: Coupling ferromagnetic and antiferromagnetic materials at the nanoscale can result in enhanced anisotropy through exchange bias effects.
