Direct observation of valence transition inCeNi1−xCoxSnalloys by x-ray and photoelectron spectroscopies

Hybridization and suppression of superconductivity inCeFeAsO1−y: Pressure and temperature dependence of the electronic structure

“…The intensity of f 2 component is multiplied by 35. To extract the intensity ratios of the different f components we have analyzed the PFY-XAS and RXES spectra. [26][27][28][29][30][31] Figure 4 shows examples of the fits for ͑a͒ the PFY-XAS spectrum and ͑b͒ the RXES spectrum at E in = 5719 eV measured for SC CeFeAsO 1−y at 300 K. In the PFY-XAS spectra after subtraction of an arctangentlike ͑asymmetrical double sigmoid͒ function corresponding to the continuum excitations, two Voigt functions are used to fit the f 1 ͑Ce 3+ ͒ and the f 2 ͑Ce 2+ ͒ components. In the fit of the RXES spectra, we use a total of four Voigt functions for f 1 and f 2 .…”

“…To carry this out, we used two complementary hard x-ray spectroscopic probes at the Ce L 3 edge, partial fluorescence yield x-ray absorption spectroscopy ͑PFY-XAS͒ and resonant x-ray emission spectroscopy ͑RXES͒. [26][27][28][29][30][31][32] The PFY-XAS technique yields spectra with sharper features than conventional absorption, offering a higher accuracy when deriving quantitative information such as the valence. We find that both the SC and the non-SC samples show a gradual increase in the valence with pressure.…”

Temperature and pressure-induced valence transitions inYbNi2Ge2andYbPd2Yamaoka1, Jarrige2, Tsujii3 et al. 2010Phys. Rev. B486560View full textAdd to dashboardCite

“…[19][20][21][22][23][24][25] RXES yields truly bulk-sensitive information about the electronic structure. It is well suited to the study of subtle pressure-induced changes in the electronic state of rare-earth compounds.…”

Electronic structure of YbGa1.15Si0.85and YbGaYamaoka1, Jarrige2, Tsujii3 et al. 2011Phys. Rev. B

“…To address this issue, we performed a detailed investigation of the electronic structure of superconducting YbGa 1. 15 Si 0.85 and nonsuperconducting YbGa x Ge 2−x (x=1.0 and 1.1), using a combination of resonant x-ray emission spectroscopy (RXES), x-ray absorption spectroscopy in the partial flu-orescence mode (PFY-XAS), [22][23][24][25][26][27][28] and soft x-ray and vacuum ultraviolet (UV) PES. 29,30 No temperature dependence of the valence was found for YbGa 1.15 Si 0.85 , while the valence was found to increase dramatically with pressure.…”