Fermi Surface of Ferromagnetic Nickel

Abstract

A survey of nonmagnetic band structures near the top of the $3d$ band is made. The aim is to combine these band structures with a wide variety of experimental data to determine the exchange splittings of the $d$ bands $\Delta E_{\mathrm{dd}}$ and the $s-p$ conduction band $\Delta E_{\mathrm{ss}}$. Saturation magnetization, $g$ factors, and high-field Hall data are analyzed and compared with the effect of $s-d$ hybridization on the number of $s$ electrons. One concludes that if the neck observed in magnetoresistance studies is associated with the same band edge as the Cu neck, $\Delta E_{\mathrm{dd}}\lesssim 0.8$ eV. It appears that $\Delta E_{\mathrm{ss}}\lesssim \frac{\Delta E_{\mathrm{dd}}}{2}$. Recent optical rotation data of Krinchik are interpreted as giving a direct measurement of $\Delta E_{\mathrm{dd}}$. The value obtained is (0.6±0.1) eV, in good agreement with the values obtained from other data.