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arXiv · 1304.2226

Intrinsic Correlated Electronic Structure of CrO2 Revealed by Hard X-ray Photoemission Spectroscopy

M. Sperlich·C. König·G. Güntherodt·A. Sekiyama·G. Funabashi·M. Tsunekawa·S. Imada·A. Shigemoto·K. Okada·A. Higashiya·M. Yabashi·K. Tamasaku·T. Ishikawa·V. Renken·T. Allmers·M. Donath·S. Suga
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Abstract

Bulk-sensitive hard x-ray photoemission spectroscopy (HAXPES) reveals for as-grown epitaxial films of half-metallic ferromagnetic CrO2(100) a pronounced screening feature in the Cr 2p3/2 core level and an asymmetry in the O 1s core level. This gives evidence of a finite, metal-type Fermi edge, which is surprisingly not observed in HAXPES. A spectral weight shift in HAXPES away from the Fermi energy is attributed to single-ion recoil effects due to high energy photoelectrons. In conjunction with inverse PES the intrinsic correlated Mott-Hubbard-type electronic structure is unravelled, yielding an averaged Coulomb correlation energy Uav ~ 3.2 eV.

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M. Sperlich, C. König, G. Güntherodt, A. Sekiyama, G. Funabashi, M. Tsunekawa, S. Imada, A. Shigemoto, K. Okada, A. Higashiya, M. Yabashi, K. Tamasaku, T. Ishikawa, V. Renken, T. Allmers, M. Donath, S. Suga. 2013-04-08. Intrinsic Correlated Electronic Structure of CrO2 Revealed by Hard X-ray Photoemission Spectroscopy. https://doi.org/10.1103/physrevb.87.235138

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