Element-resolved study on the evolution of magnetic response in FexN compounds

A systematic XMCD analysis was performed to study the evolution of magnetic moments of overall Fe atoms in alpha'-FexN thin films. It was found that the spin and orbital moments of overall Fe 3d shell of alpha'-FexN increase gradually along c-axis with increasing nitrogen fraction. We showed that the magnetocrystalline anisotropy of alpha'-FexN compounds is associated with corresponding orbital anisotropy of Fe 3d shell. No clear p-d hybridization between Fe and N elements was discovered in the current experimental systems, suggesting that lattice expansion has a sufficient influence on magnetic performance of alpha'-Fe8N compounds