The HgBa2CuO4+delta superconductor has been studied by high resolution Hg L-3 x-ray absorption near-edge structure (XANES) spectroscopy. The XANES spectrum has been simulated by full multiple-scattering calculations in order to explore the origin of different features in the experimental spectrum. The experimental Hg L-3-edge spectrum could be well reproduced by considering a cluster of 85 atoms, containing 10 shells, within a radius of about 7 Angstrom from the central Hg atom. The low energy spectral feature in the XANES spectrum is found to be due to a transition from the Hg p states to the electronic states hybridized with higher shell Ba atoms. This implies that the transition features in the Hg L3-edge XANES are strongly influenced by medium range order effects unlike the case of L-3 edge of 3d transition metals where short-range order is enough to describe the main transition features.
Hg L3 edge absorption study of the HgBa2Cu04+ d superconductor / Z., Wu; Saini, Naurang Lal; Bianconi, Antonio. - In: PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS. - ISSN 1098-0121. - STAMPA. - 64:(2001), pp. 092507-1-092507-4. [10.1103/PhysRevB.64.092507]
Hg L3 edge absorption study of the HgBa2Cu04+ d superconductor
SAINI, Naurang Lal;BIANCONI, Antonio
2001
Abstract
The HgBa2CuO4+delta superconductor has been studied by high resolution Hg L-3 x-ray absorption near-edge structure (XANES) spectroscopy. The XANES spectrum has been simulated by full multiple-scattering calculations in order to explore the origin of different features in the experimental spectrum. The experimental Hg L-3-edge spectrum could be well reproduced by considering a cluster of 85 atoms, containing 10 shells, within a radius of about 7 Angstrom from the central Hg atom. The low energy spectral feature in the XANES spectrum is found to be due to a transition from the Hg p states to the electronic states hybridized with higher shell Ba atoms. This implies that the transition features in the Hg L3-edge XANES are strongly influenced by medium range order effects unlike the case of L-3 edge of 3d transition metals where short-range order is enough to describe the main transition features.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.