669 research outputs found

    An Unfinished Canvas: Teacher Preparation, Instructional Delivery, and Professional Development in the Arts

    Get PDF
    Based on surveys, interviews, and secondary data analyses, identifies deficiencies in teacher preparation, instruction, and development in the arts in California, and recommends minimum training requirements and support for professional development

    X-ray induced electronic structure change in CuIr2_2S4_4

    Full text link
    The electronic structure of CuIr2_2S4_4 has been investigated using various bulk-sensitive x-ray spectroscopic methods near the Ir L3L_3-edge: resonant inelastic x-ray scattering (RIXS), x-ray absorption spectroscopy in the partial fluorescence yield (PFY-XAS) mode, and resonant x-ray emission spectroscopy (RXES). A strong RIXS signal (0.75 eV) resulting from a charge-density-wave gap opening is observed below the metal-insulator transition temperature of 230 K. The resultant modification of electronic structure is consistent with the density functional theory prediction. In the spin- and charge- dimer disordered phase induced by x-ray irradiation below 50 K, we find that a broad peak around 0.4 eV appears in the RIXS spectrum.Comment: 4 pages and 4 figure

    Resonant inelastic X-ray scattering study of overdoped La2−x_{2-x}Srx_{x}CuO4_{4}

    Full text link
    Resonant inelastic x-ray scattering (RIXS) at the copper K absorption edge has been performed for heavily overdoped samples of La2−x_{2-x}Srx_{x}CuO4_{4} with x=0.25x= 0.25 and 0.30. We have observed the charge transfer and molecular-orbital excitations which exhibit resonances at incident energies of Ei=8.992E_i= 8.992 and 8.998 keV, respectively. From a comparison with previous results on undoped and optimally-doped samples, we determine that the charge-transfer excitation energy increases monotonically as doping increases. In addition, the EiE_i-dependences of the RIXS spectral weight and absorption spectrum exhibit no clear peak at Ei=8.998E_i = 8.998 keV in contrast to results in the underdoped samples. The low-energy (≤3\leq 3 eV) continuum excitation intensity has been studied utilizing the high energy resolution of 0.13 eV (FWHM). A comparison of the RIXS profiles at (π 0)(\pi ~0) and (π π)(\pi ~\pi) indicates that the continuum intensity exists even at (π π)(\pi ~\pi) in the overdoped samples, whereas it has been reported only at (0 0)(0 ~0) and (π 0)(\pi ~0) for the x=0.17x=0.17 sample. Furthermore, we also found an additional excitation on top of the continuum intensity at the (π π)(\pi ~\pi) and (π 0)(\pi ~0) positions.Comment: 7 pages, 7 figure
    • …
    corecore