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The ultrathin Co x Ni 1Ϫx /Cu(100) alloy films with low Co concentration xр10% was prepared for probing the effect of the d-band filling on the magnetic behavior. The perpendicular magnetization was observed only for films with xϽ10%. The spin-reorientation transition from the in-plane to perpendicular orientation was found to be extremely sensitive to the Co concentration. The critical thickness for the spin reorientation transition was changed drastically from 7.5 to 17.5 ML by varying x from 0 to 8 %. Since no significant change in structure and surface morphology was accompanied, these findings may be attributed to the critical influence of the d-band filling on the magnetic anisotropy at variation of alloy composition.

Electronic structures of strained Nd 1−x Ca x MnO 3 ͑NCMO͒ thin films with x = 0 to 0.8 are investigated via x-ray absorption spectroscopy ͑XAS͒. The obtained O 1s spectra within the photon energy 529-535 eV can be decomposed into e g ↑ 1 , e g ↑ 2 , t 2g ↓, and e g ↓ bands. Based on the assigned energy levels of these band states, the energies of magnetic exchange, crystal field and Jahn-Teller ͑JT͒ splitting are determined. Particularly, the JT splitting is around 0.8 eV, which is observed with O 1s XAS for the first time in NCMO thin films.

A partially ordered Fe16N2 thin film, which exhibits a higher saturation magnetization than a bcc-Fe thin film, was grown on a Au(001) texture on a GaAs(001) substrate for studies of crystalline structure, electronic structure, and magnetic properties. Fe 2p3/2 and 2p1/2 X-ray photoelectron spectroscopies (XPS) reveal the electronic hybridization between the Fe atoms and the adjacent N atoms, whereas a multipeak analysis suggests the charge-transfer-induced electronic rearrangement of electronic configuration in Fe(8h) and Fe(4e) geometrical sites. These results are consistent with the previous model and help explain the saturation magnetization enhancement in the α-FeN system.