Direct Evidence of the Role of Hybridization in the X-Ray Magnetic Circular Dichroism of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>α</mml:mi></mml:math>-Ce

Abstract

We present an x-ray magnetic circular dichroism (XMCD) study of a [Ce(10 \AA{})/Fe(30 \AA{})] multilayer performed at the Ce-${M}_{4,5}$ absorption edges. In this system the Ce-$4f$ electrons are strongly hybridized with the valence band. XMCD experiments show that they carry an ordered magnetic moment. The differences of the shape of the XMCD signals of a typical $\ensuremath{\gamma}$-like compound (CeCuSi) and of the Ce/Fe multilayer highlight the role of hybridization in determining the ground state of cerium atoms in the multilayer, which results in a mixing of $J=\frac{5}{2}$ and $J=\frac{7}{2}$ coupled states.