Journal or Book Title
Physical Review B
Ellipsometric measurements of the complex dielectric functions of Ni and Ni1−cCuc alloys (c=0.1,0.3,0.4) have been carried out in the (1.2–5.5)-eV region. Two structures in the σ1 spectrum of pure Ni at about 1.5 and 4.7 eV are attributable to direct interband transitions in the band structure of ferromagnetic Ni. As the Cu concentration increases, the 4.7-eV edge (from transitions between the s-d–hybridized bands well below EF and the s-p-like bands above EF, e.g., X1→X’4) shifts to higher energies, while the 1.5-eV edge (from transitions between a p-like band below EF and a dband above EF along the L–W direction, e.g., L’2→L3) remains at the same energy. A structure grows in the (2–3)-eV region as Cu is added, and it is interpreted to be due to the transitions between the localized Cu subbands. All these observations are in accord with the calculated (coherent-potential-approximation) electronic structure of Ni-Cu alloys.
The American Physical Society
Kim, Kwang-Joo and Lynch, David W., "Electronic structure of Ni-Cu alloys studied by spectroscopic ellipsometry" (1989). Physics and Astronomy Publications. 71.