Band-structure and core-hole effects in resonant inelastic soft-x-ray scattering: Experiment and theory

Journal Article · Mon Mar 01 04:00:00 EST 1999 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.59.7433· OSTI ID:321982

Carlisle, J A ^[1]; Shirley, E L ^[2]; Terminello, L J ^[3]; Jia, J J; Callcott, T A ^[4]; Ederer, D L ^[5]; Perera, R C ^[6]; Himpsel, F J ^[7]

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1. Virginia Commonwealth University, Richmond, Virginia 23284 (United States)
2. National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)
3. Lawrence Livermore National Laboratory, Livermore, California 94551 (United States)
4. University of Tennessee, Knoxville, Tennessee 37996 (United States)
5. Tulane University, New Orleans, Louisiana 70118 (United States)
6. Center for X-ray Optics, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)
7. University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States)

Inelastic x-ray scattering has been observed in the hexagonal forms of carbon (graphite) and boron nitride (hBN), both above and below their K edges. For excitation energies {ital below} the core threshold, inelastic-loss features are observed, which disperse {ital linearly} with excitation energy (Raman-like behavior). However, {ital above} the threshold, emission features that move in a {ital nonlinear} fashion are observed. We show that these two scattering regimes, which have previously been thought of as separate processes, viz., resonant x-ray Raman scattering (below threshold) and resonant inelastic x-ray scattering (above threshold), are described by the same theory for resonant fluorescence. Simulated spectra, with and without excitonic effects, are presented and compared with experiment. We conclude, based on this comparison, that excitonic effects influence these spectra in two ways. Primarily, the total fluorescence yields are enhanced or reduced simply because of changes in the absorption cross sections. Second, excitonic effects on emission features can be pronounced near some excitonic resonances, and these changes are more significant for excitation further above the K edges, which we attribute to the multiplicity of core-excited states being probed. Based on these findings, we conclude that core-hole effects do not necessarily undermine an interpretation of the scattering in terms of a one-electron (noninteracting) picture, and that resonant fluorescence spectroscopy may be successfully used to probe the band structure of solids. {copyright} {ital 1999} {ital The American Physical Society}

• OSTI ID: 321982
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 11 Vol. 59; ISSN 0163-1829; ISSN PRBMDO
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
66 PHYSICS
BORON COMPOUNDS
BORON NITRIDES
CARBON
ELECTRONIC STRUCTURE
EXCITONS
FLUORESCENCE
GRAPHITE
HEXAGONAL LATTICES
INELASTIC SCATTERING
RESONANCE
SIMULATION
SOFT X RADIATION