RESUMEN
We report on a new method to determine the degree of bulk spin polarization in single crystal Co(1-x)Fe(x)S2 by modeling magnetic Compton scattering with ab initio calculations. Spin-dependent Compton profiles were measured for CoS2 and Co0.9Fe0.1S2. The ab initio calculations were then refined by rigidly shifting the bands to provide the best fit between the calculated and experimental directional profiles for each sample. The bulk spin polarizations, P, corresponding to the spin-polarized density of states at the Fermi level, were then extracted from the refined calculations. The values were found to be P=-72+/-6% and P=18+/-7% for CoS2 and Co0.9Fe0.1S2, respectively. Furthermore, determinations of P weighted by the Fermi velocity (v(F) or v(F)2) were obtained, permitting a rigorous comparison with other experimental data and highlighting the experimental dependence of P on v(F).
RESUMEN
The spin-dependent momentum density of Gd(7)Pd(3) was probed by the magnetic Compton scattering technique with elliptically polarized synchrotron radiation. A contribution to the spin moment from Pd 4d electrons was observed, at 2 and 280 K, alongside a large Gd 4f moment and a smaller Gd 5d moment. The total spin moment, at 2 K, was determined as 50.8 ± 0.7 µ(B) (f.u.)(-1). The Gd 4f contribution to the spin moment was determined as 43.4 ± 1.8 µ(B) (f.u.)(-1), the Gd 5d moment as 4.4 ± 0.7 µ(B) (f.u.)(-1) and the Pd 4d spin moment contribution as 2.9 ± 1.1 µ(B) (f.u.)(-1), where f.u. represents a formula unit. At 280 K the total spin moment was 27.3 ± 0.9 µ(B) (f.u.)(-1) with individual contributions determined as a Gd 4f spin moment of 23.8 ± 1.1 µ(B) (f.u.)(-1), a Gd 5d contribution of 2.2 ± 0.5 µ(B) (f.u.)(-1) and a Pd 5d spin moment of 1.2 ± 0.6 µ(B) (f.u.)(-1).