Observation of resonant Raman scattering at the SiL2,3core exciton

Abstract

The resonant soft-x-ray emission spectra at the Si L 2,3 core exciton have been measured at 18 K by using synchrotron radiation. As an excitation light source, a very high-resolution monochromator with the undulator was used. The Raman scattering whose energy shifts in proportion to the excitation energy is found below the L 2,3 absorption edge. The intensity of the Raman scattering increases rapidly as the excitation energy comes close to the L 2,3 core exciton. It is found that the Raman scattering resonates at the L 2,3 core exciton which is made around the X 1 conduction minimum. The elementary excitation of the Raman scattering is the valence exciton that is a transition from X 1 or X 4 points in the valence band to the X 1 conduction minimum. The X 4 valence exciton has a characteristic excitation-energy dependence, so that it becomes broad and weak as the resonant Raman process goes to the ordinary Raman process.

Theoretical analysis of the magnetic circular dichroism in the2p3dand2p4dx-ray emission of Gd

“…These trends are reproduced at the 2 p 3/2 3d 3/2 transition at Ϫ6025 eV. Only four 8 S-related sticks are visible, because 3d 3/2 only couples with 8 S to J f ϭ2,3,4,5. The MCD is reversed due to reversed energy ordering of the J f states, visible also in the increasing intensity with J f .…”

“…5͒ and the 2 p3d resonant x-ray emission. [6][7][8][9][10] In the case of rare earth systems, experiments include the 3d4 f and 4d4 f resonant x-ray emission, 11,12 and the 2p3d and 2p4d resonant x-ray emission. [13][14][15] A few studies have been carried out with the use of circular polarization.…”

Resonant soft-x-ray emission study in relation to the band structure of cBN

“…Recently, SXES studies have been performed by means of the inelastic-light-scattering process using high-brilliance synchrotron radiation as an excitation light source. [1][2][3][4][5][6][7][8] Using synchrotron radiation, one can utilize the excitation energy dependence of the SXES, which provides an experimental method to understand the electronic structure of matters in relation to the band structure.…”

“…[1][2][3][4][5][6][7] This is the resonant fluorescence or the inelastic lightscattering process, where the wave vector of the valence hole is the same as that of the excited electron. Thus, momentumresolved inelastic light scattering offers a band mapping technique.…”

X-ray Fluorescence Spectroscopy of Novel Materials

“…This was interpreted in terms of correlation between the momentum of the photoelectron and that of the valence-band hole in the final state, which augmented the emission in the symmetrical points of the Brillouin zone to which the electron was excited from a core level [25][26][27]. In connection with this, it was proposed that RIXS spectra should be treated in terms of a single inelastic scattering process with no changes in k momentum, which laid a foundation for studies of band dispersion in crystals by the method under consideration (see also [28,29]). The first comparison of the band dispersion inferred from RIXS measurements with that evaluated theoretically was reported by Luning et al [30] for SiC.…”