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C Laubschat

Publications and source records attributed to C Laubschat.

At least 19 recordsLinked to original sources
PubMed2006

Energy dispersion of 4f-derived emissions in photoelectron spectra of the heavy-fermion compound YbIr2Si2.

Angle-resolved photoemission spectra of the heavy-fermion system YbIr(2)Si(2) are reported that reveal strong momentum (k) dependent splittings of the 4f(13) bulk and surface emissions around the expected intersection points of the 4f final states with valence bands in the Brillouin zone. The obtained dispersion is explained in terms of a simplified periodic Anderson model by a k dependence of the electron hopping matrix element disregarding clearly interpretation in terms of a single-impurity model.

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PubMed2006

Wave-vector conservation upon hybridization of 4f and valence-band states observed in photoemission spectra of a Ce monolayer on W(110).

Angle-resolved resonant photoemission data for a hexagonally ordered monolayer of Ce on W(110) are presented. The spectra reveal a splitting of the 4f(0) ionization peak around a point in k space where a degeneracy with a valence-band state is expected. The phenomenon is described within a simple approach to the periodic Anderson model. It is found that the Ce 4f state forms a band and hybridization predominantly occurs between the 4f and the valence-band states at the same wave vector.

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PubMed2001

Interpretation of resonant photoemission spectra of solid actinide systems.

It is shown that valence-band photoemission (PE) spectra of epitaxial hcp films of U metal may be understood within a one-step model of PE based on an itinerant description of the U 5f states. Particularly, the PE intensities of the f-derived bands are correctly reproduced for photon energies between 60 and 103 eV. It is found that a cross-section minimum of the Fermi-energy feature at h(nu) = 90-94 eV, which previously was assigned to a Fano antiresonance at the 5d-->5f excitation threshold, is mainly caused by a Cooper minimum. Analogous 5f cross-section variations in the region of the 5d-->5f resonances were obtained for UPd3 and Pu metal.

Journal Article↗
PubMed2000

Cooper minima in the photoemission spectra of solids.

Variations of the photoionization cross section of valence states as a function of interatomic distance are studied by means of atomic and solid-state density functional approaches and compared with photoemission data. In contrast to the free atom case, a series of Cooper minima is found for 4d, 5d, and 5f states in Pd, Ag, Au, and U metals. The discovered fundamental phenomenon is of high importance for the correct interpretation of photoemission data.

Journal Article↗