Influence of anti-site disorder and electron-electron correlations on the electronic structure of CeMnNi${}_4$

Abstract

CeMnNi${}_4$ exhibits an unusually large spin polarization, but its origin has baffled researchers for more than a decade. We use bulk sensitive hard x-ray photoelectron spectroscopy (HAXPES) and density functional theory based on the Green's function technique to demonstrate the importance of electron-electron correlations of both the Ni 3$d$ ($U_{Ni}$) and Mn 3$d$ ($U_{Mn}$) electrons in explaining the valence band of this multiply correlated material. We show that Mn-Ni anti-site disorder as well as $U_{Ni}$ play crucial role in enhancing its spin polarization: anti-site disorder broadens a Ni 3$d$ minority-spin peak close to the Fermi level ($E_F$), while an increase in $U_{Ni}$ shifts it towards $E_F$, both leading to a significant increase of minority-spin states at $E_F$. Furthermore, rare occurrence of a valence state transition between the bulk and the surface is demonstrated highlighting the importance of HAXPES in resolving the electronic structure of materials unhindered by surface effects.

arXiv commentManuscript and Supplementary material, 13 pages, 17 figures

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Cited by in corpus (3)

• Electronic structure of Au-Sn compounds grown on Au(111)
• Bulk Electronic Structure of Ni2MnGa studied by Density Functional Theory and Hard X-ray Photoelectron Spectroscopy
• Intrinsic and extrinsic plasmons in the hard x-ray photoelectron spectra of nearly free electron metals