The Experts below are selected from a list of 201 Experts worldwide ranked by ideXlab platform
D.s.l. Law - One of the best experts on this subject based on the ideXlab platform.
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High resolution X-Ray Photoemission of SrCu2O2
Chemical Physics Letters, 2005Co-Authors: C.c.b. Lynch, R. G. Egdell, D.s.l. LawAbstract:Pure and K-doped SrCu 2O 2 have been studied by high resolution X-Ray Photoemission spectroscopy. Valence band Photoemission spectra are shown to be in good agreement with the bandstructure calculations of Ohta et al. and are dominated by the Cu 3d partial density of states. Conductivity measurements reveal that the Fermi level in nominally undoped material is pinned by acceptor states 0.24 eV above the valence band edge but moves toward the valence band with increasing doping. Changes in core and valence level binding energies with doping mirror the changes in the transport activation energy. © 2004 Elsevier B.V. All rights reserved
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High resolution X-Ray Photoemission of SrCu2O2
Chemical Physics Letters, 2004Co-Authors: C.c.b. Lynch, R. G. Egdell, D.s.l. LawAbstract:Abstract Pure and K-doped SrCu 2 O 2 have been studied by high resolution X-Ray Photoemission spectroscopy. Valence band Photoemission spectra are shown to be in good agreement with the bandstructure calculations of Ohta et al. and are dominated by the Cu 3d partial density of states. Conductivity measurements reveal that the Fermi level in nominally undoped material is pinned by acceptor states 0.24 eV above the valence band edge but moves toward the valence band with increasing doping. Changes in core and valence level binding energies with doping mirror the changes in the transport activation energy.
C.c.b. Lynch - One of the best experts on this subject based on the ideXlab platform.
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High resolution X-Ray Photoemission of SrCu2O2
Chemical Physics Letters, 2005Co-Authors: C.c.b. Lynch, R. G. Egdell, D.s.l. LawAbstract:Pure and K-doped SrCu 2O 2 have been studied by high resolution X-Ray Photoemission spectroscopy. Valence band Photoemission spectra are shown to be in good agreement with the bandstructure calculations of Ohta et al. and are dominated by the Cu 3d partial density of states. Conductivity measurements reveal that the Fermi level in nominally undoped material is pinned by acceptor states 0.24 eV above the valence band edge but moves toward the valence band with increasing doping. Changes in core and valence level binding energies with doping mirror the changes in the transport activation energy. © 2004 Elsevier B.V. All rights reserved
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High resolution X-Ray Photoemission of SrCu2O2
Chemical Physics Letters, 2004Co-Authors: C.c.b. Lynch, R. G. Egdell, D.s.l. LawAbstract:Abstract Pure and K-doped SrCu 2 O 2 have been studied by high resolution X-Ray Photoemission spectroscopy. Valence band Photoemission spectra are shown to be in good agreement with the bandstructure calculations of Ohta et al. and are dominated by the Cu 3d partial density of states. Conductivity measurements reveal that the Fermi level in nominally undoped material is pinned by acceptor states 0.24 eV above the valence band edge but moves toward the valence band with increasing doping. Changes in core and valence level binding energies with doping mirror the changes in the transport activation energy.
R. G. Egdell - One of the best experts on this subject based on the ideXlab platform.
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Electronic structure of In2O3 and Sn-doped In2O3 by hard X-Ray Photoemission spectroscopy
Physical Review B, 2010Co-Authors: Christoph Körber, Piero Torelli, G. Panaccione, R. G. Egdell, V. Krishnakumar, Andreas Klein, Aron Walsh, J.l.f. Da Silva, Su Huai Wei, David J. PayneAbstract:The valence and core levels of In(2)O(3) and Sn-doped In(2)O(3) have been studied by hard X-Ray Photoemission spectroscopy (hv = 6000 eV) and by conventional Al K alpha (hv = 1486.6 eV) X-Ray Photoemission spectroscopy. The experimental spectra are compared with density-functional theory calculations. It is shown that structure deriving from electronic levels with significant In or Sn 5s character is selectively enhanced under 6000 eV excitation. This allows us to infer that conduction band states in Sn-doped samples and states at the bottom of the valence band both contain a pronounced In 5s contribution. The In 3d core line measured at hv = 1486.6 eV for both undoped and Sn-doped In(2)O(3) display an asymmetric lineshape, and may be fitted with two components associated with screened and unscreened final states. The In 3d core line spectra excited at hv = 6000 eV for the Sn-doped samples display pronounced shoulders and demand a fit with two components. The In 3d core line spectrum for the undoped sample can also be fitted with two components, although the relative intensity of the component associated with the screened final state is low, compared to excitation at 1486.6 eV. These results are consistent with a high concentration of carriers confined close to the surface of nominally undoped In(2)O(3). This conclusion is in accord with the fact that a conduction band feature observed for undoped In(2)O(3) in Al K alpha X-Ray Photoemission is much weaker than expected in hard X-Ray Photoemission.
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A study of core and valence levels in β-PbO2 by hard X-Ray Photoemission
Journal of Electron Spectroscopy and Related Phenomena, 2009Co-Authors: David J. Payne, Francesco Offi, Giulio Monaco, A. Fondacaro, G. Panaccione, G Paolicelli, Paolo Lacovig, Graham Beamson, György Vankó, R. G. EgdellAbstract:Abstract The core and valence levels of β-PbO 2 have been studied using hard X-Ray Photoemission spectroscopy ( hν = 6000 eV and 7700 eV). The Pb 4f core levels display an asymmetric lineshape which may be fitted with components associated with screened and unscreened final states. It is found that intrinsic final state screening is suppressed in the near-surface region. A shift in the O 1s binding energy due to recoil effects is observed under excitation at 7700 eV. It is shown that conduction band states have substantial 6s character and are selectively enhanced in hard X-Ray Photoemission spectra. However, the maximum amplitude in the Pb 6s partial density of states is found at the bottom of the valence band and the associated Photoemission peak shows the most pronounced enhancement in intensity at high photon energy.
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High resolution X-Ray Photoemission of SrCu2O2
Chemical Physics Letters, 2005Co-Authors: C.c.b. Lynch, R. G. Egdell, D.s.l. LawAbstract:Pure and K-doped SrCu 2O 2 have been studied by high resolution X-Ray Photoemission spectroscopy. Valence band Photoemission spectra are shown to be in good agreement with the bandstructure calculations of Ohta et al. and are dominated by the Cu 3d partial density of states. Conductivity measurements reveal that the Fermi level in nominally undoped material is pinned by acceptor states 0.24 eV above the valence band edge but moves toward the valence band with increasing doping. Changes in core and valence level binding energies with doping mirror the changes in the transport activation energy. © 2004 Elsevier B.V. All rights reserved
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High resolution X-Ray Photoemission of SrCu2O2
Chemical Physics Letters, 2004Co-Authors: C.c.b. Lynch, R. G. Egdell, D.s.l. LawAbstract:Abstract Pure and K-doped SrCu 2 O 2 have been studied by high resolution X-Ray Photoemission spectroscopy. Valence band Photoemission spectra are shown to be in good agreement with the bandstructure calculations of Ohta et al. and are dominated by the Cu 3d partial density of states. Conductivity measurements reveal that the Fermi level in nominally undoped material is pinned by acceptor states 0.24 eV above the valence band edge but moves toward the valence band with increasing doping. Changes in core and valence level binding energies with doping mirror the changes in the transport activation energy.
Carsten Westphal - One of the best experts on this subject based on the ideXlab platform.
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Hard X-Ray Photoemission spectroscopy on the trilayer system MgO/Au/Fe using standing-wave excitation
Journal of Physics D: Applied Physics, 2013Co-Authors: Sven Döring, Claus M. Schneider, F. Schönbohm, U. Berges, Daniel E. Bürgler, Mihaela Gorgoi, Franz Schäfers, Carsten WestphalAbstract:The trilayer system MgO/Au monolayer/Fe was investigated by hard X-Ray Photoemission experiments in combination with the standing-wave technique. The insertion of the Au layer into the Fe/MgO tunnel junction provides an additional handle to influence the properties of the interface. The recently explored method of standing-wave excited hard X-Ray Photoemission was used to investigate both the structural properties and chemical states of the interfacial layers in one experiment. The results show that the Au monolayer does not grow as a closed layer, but intermixes strongly with the Fe below. This behaviour results in a very sharp interface between the Au/Fe and the MgO layer on top. However, the XPS spectra show no hint for a formation of FeO at the interface.
Gunnar Karl Palsson - One of the best experts on this subject based on the ideXlab platform.
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accurate determination of the valence band edge in hard x ray Photoemission spectra using gw theory
Journal of Applied Physics, 2016Co-Authors: Johannes Lischner, Giuseppina Conti, Andrei Gloskovskii, Slavomír Nemšák, Gunnar Karl PalssonAbstract:We introduce a new method for determining accurate values of the valence-band maximum in X-Ray Photoemission spectra. Specifically, we align the sharpest peak in the valence-band region of the experimental spectrum with the corresponding feature of a theoretical valence-band density of states curve from ab initio GW theory calculations. This method is particularly useful for soft and hard X-Ray Photoemission studies of materials with a mixture of valence-band characters, where strong matrix element effects can render standard methods for extracting the valence-band maximum unreliable. We apply our method to hydrogen-terminated boron-doped diamond, which is a promising substrate material for novel solar cell devices. By carrying out Photoemission experiments with variable light polarizations, we verify the accuracy of our analysis and the general validity of the method.
