Angle resolved photoemission

Plummer E W and Eberhardt W 1982 Angle-resolved photoemission as a tool for the study of surfaces Adv. Chem. Rhys. 49 533... 

Volume 74 Angle-Resolved Photoemission. Theory and Current Applications edited by S.D. Kevan... 

Thus, in addition to the dispersion itself, we get information about which band is occupied in which Brillouin zone. This is a consequence of the fact that EMS measures real momentum, and not, like for example angle-resolved photoemission, crystal momentum. 

Detailed electronic energy-band calculations have revealed the existence of appropriate surface states near the Fermi energy, indicative of an electronically driven surface instability. Angle-resolved photoemission studies, however, showed that the Fermi surface is very curved and the nesting is far from perfect. Recently Wang and Weber have calculated the surface phonon dispersion curve of the unreconstructed clean W(100) surface based on the first principles energy-band calculations of Mattheis and Hamann. ... 

The problem of first-principles calculations of the electronic structure of solid surface is usually formatted as a problem of slabs, that is, consisting of a few layers of atoms. The translational and two-dimensional point group symmetry further reduce the degrees of freedom. Using modern supercomputers, such first-principles calculations for the electronic structure of solid surfaces have produced remarkably reproducible and accurate results as compared with many experimental measurements, especially angle-resolved photoemission and inverse photoemission. 

Two rather different techniques that exploit the same underlying phenomenon of coherent interference of elastically scattered low energy electrons are photoelectron diffraction [5] and surface extended X-ray absorption fine structure (SEXAFS) [6,7]. Figure 1.1. shows schematically a comparison of the electron interference paths in LEED and in these two techniques. In both photoelectron diffraction and SEXAFS the source of electrons is not an electron beam from outside the surface, as in LEED, but photoelectrons emitted from a core level of an atom within the adsorbate. In photoelectron diffraction one detects the photoelectrons directly, outside the surface, as a function of direction or photoelectron energy (or both). The detected angle-resolved photoemission signal comprises a coherent sum of the directly emitted component of the outgoing photoelectron wavefield and other components of the same wavefield elastically scattered by atoms (especially in the substrate) close... 

S. D. Kevan, Angle-resolved photoemission. (Elsevier, Amsterdam, 1992). 

Fink, A., Huber, R. and Widdra, W. Ethylene adsorption on Ge(100)-(2 x 1) A combined angle-resolved photoemission and thermal desorption spectroscopy study. Journal of Chemical Physics 115, 2768-2775 (2001). 

L.I. Johansson and C.G. Larsson. Angle Resolved Photoemission, S.D. Kevan, Ed., (Springer, 1992), Chap. 8 and references therein. 

It is remarkable that both quantities show very similar temperature dependences. It means that our microscopic EPR measurements and the macroscopic resistivity measurements by Ando et al. provide evidence of the same phenomenon the formation of hole-rich metallic stripes in lightly doped LSCO well below xcr = 0.06. This conclusion is also supported by a recent angle-resolved photoemission (ARPES) study of LSCO which clearly demonstrated that the metallic quasiparticles exist near the nodal direction below x=0.06 [16],... 

M. Schabel and Z.-X. Shen, Angle-resolved photoemission studies of untwinned yttrium barium copper oxide 391... 

Angle - resolved photoemission extended fine structure. 

The lower panel of Fig. 4 reproduces angle-resolved photoemission spectra [43] showing the dispersion of the state, i.e. how its BE changes with the angle of emission with respect to the normal. The dotted line in Fig. 3 shows schematically the E(k ) upwards parabolic dispersion of the surface state. The Binding Energy (BE) of the Cu(lll) surface state at the center of the 2D Brillouin Zone (BZ) is —400 meV relative to the Fermi energy. The effective mass for the electrons in this state is obtained from the curvature... 

Y. Enta, S. Suzuki and S. Kono, Angle-resolved-photoemission study of the electronic structure of the Si(100)c(4x 2) surface, Phys. Rev. Lett. 65, 2704 (1990). 

L. S. O. Johansson, R. I. G. Uhrberg, P. Martensson and G. V. Hansson, Surface-state band structure of the Si(100)2 x 1 surface studied with polarization-dependent angle-resolved photoemission on single domain surfaces, Phys. Rev. B 42, 1305 (1990). 

Mazin, 1.1. and S. L. Molodtsov. 2005. Electrons and phonons in YbC6 Density functional calculations and angle-resolved photoemission measurements. Phys. Rev. B 72 172504-1-4. 

The chemisorption bond between CO or NO and Pt is mainly attributed to the interaction of a electron of the adsorbate with the d hole of Pt, whereas the site selection of the adsorbate is assisted by the interaction between the adsorbate 2tt and the Pt 5d orbital. The shape of the d orbital is important for this site selection. The five d orbitals in the Oh space group are generally classified into eg (dx2 y2 and d3,2 r2) and r2g (dxy, dyz, and dM) orbitals with respect to the cubic coordinate. Of the two states of Pt, t2g has more d hole character [90], and furthermore, only the f2g state is upward-shifted and the eg is preferentially filled as a result of s-d hybridization [89]. The d band filling in the eg state due to the s-d hybridization for the alloy is supported by the band structure of this alloy in the Y-L direction observed by angle-resolved photoemission spectroscopy using synchrotron radiation [88]. 

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