PROBING THE GRAPHITE BAND STRUCTURE WITH RESONANT SOFT-X-RAY FLUORESCENCE

摘要: Soft x-ray fluorescence (SXF) spectroscopy using synchrotron radiation offers several advantages over surface sensitive spectroscopies for probing the electronic structure of complex multi-elemental materials. Due to long mean free path photons in solids ({approximately}1000 {angstrom}), SXF is a bulk-sensitive probe. Also, since core levels are involved absorption and emission, both element- angular-momentum-selective. measures local partial density states (DOS) projected onto each constituent element material. The chief limitation has been low yield photon particularly light elements. However, third generation sources, such as Advanced Light Source (ALS), offer high brightness that makes high-resolution experiments practical. In following authors utilize this demonstrate capability probe band polycrystalline sample. SXF, valence emission spectrum results from transitions hole produced by incident photons. non-resonant energy regime, excitation far above binding energy, events uncoupled. resembles spectra acquired energetic electrons, insensitive incidentmore » photon`s energy. resonant electrons excited unoccupied just Fermi level (EF). coupled, coupling manifests itself ways, depending part on localization empty Here report spectral measurements highly oriented pyrolytic graphite.« less