Europhys. Lett.
Volume 74, Number 1, April 2006
Page(s) 117 - 123
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 22 February 2006
Europhys. Lett., 74 (1), pp. 117-123 (2006)
DOI: 10.1209/epl/i2005-10498-x

High-field magnetic susceptibility of $\chem{Fe_{1-{\it x}}Co_{\it x}}$ alloys

S. Mankovsky and H. Ebert

Department Chemie und Biochemie/Physikalische Chemie, Universität München Butenandtstr. 5-13, D-81377 München, Germany

received 2 December 2005; accepted in final form 3 February 2006
published online 22 February 2006

A fully relativistic theoretical description of the magnetic high-field susceptibility of disordered alloys is presented. This approach not only accounts for the Pauli spin and Van Vleck orbital susceptibilities considered so far in this context, but also for the spin-orbit-induced contributions as well as the Landau susceptibility. Applications to $\chem{Fe_{1-{\it x}}Co_{\it x}}$ alloys led to a very good agreement with experiment for the Fe-rich side of the system. This also applies for the middle concentration regime if partial ordering of the samples is accounted for in the calculations. In contrast to prior investigations on the ferromagnets Fe, Co, and Ni, that considered only the Pauli spin susceptibility, it could be shown that the orbital Van Vleck and Landau contributions to the susceptibility dominate.

71.15.-m - Methods of electronic structure calculations.
75.30.Cr - Saturation moments and magnetic susceptibilities.
75.20.En - Metals and alloys.

© EDP Sciences 2006