SRC Users' Meeting - Synchrotron Radiation Center - University of ...

More documents

Recommendations

Info

References [1] S. Cho, Y. Kim, A. Di Venere, et al., Journal of Vacuum Science & technology A: Vacuum Surfaces and Films 17, 2987 (1999). [2] X. Sun, Z. Zhang, and M. S. Dresselhaus, Applied . Physics Letters 74, 4005 (1999). [3] L. M. Falicov and P. J. Lin, Physical Review 141, 562 (1966). [4] J. Rose and R. Schuchardt, Physica Status Solidi (b) 117, 213 (1983). [5] Y. Liu and R. E. Allen, Physical Review B 52, 1566 (1995). [6] X. Gonze, J. P. Michenaud, and J. P. Vigneron, Physical Review B 41, 11827 (1990). [7] C. R. Ast and H. Höchst, Physical Review Letters 77, 177602 (2001) [8] C. R. Ast and H. Höchst, Physical Review B 66, 125103 (2002). [9] C.R. Ast and H. Höchst, Physical Review Letters 90, 016403 (2003) Fig.1 : Fermi level intensity map I(k || ) of Sb(111) measured at hv=25 eV Fig.2: Fermi level intensity map I(k ,k || ) of Sb(111). The perpendicular electron momentum k was changed by scanning the photon energy from 14-28 eV.
MOMENTUM DEPENDENT LOW ENERGY LOSSES IN CORE LEVEL PHOTOEMISSION SPECTRA OF POORLY CONDUCTING METALS? Hartmut Höchst and Christian R. Ast Synchrotron Radiation Center, University of Wisconsin-Madison 3731 Schneider Drive, Stoughton, WI, 53589 The availability of high-quality samples having low impurity levels and good structural quality combined with instrumental improvements in synchrotron radiation beam lines and electron energy analyzers of high energy resolution led recently to photoemission core-level spectra exhibiting additional features which were previously not seen. Photoemission line-shape changes or multiple core-level components can occur through surface modifications, crystal-field splitting, vibrational contributions and excitations of electrons or phonons. [1] The theory of core-level photoemission and aspects of intrinsic and extrinsic excitations associated with the photo-hole, or photoelectron, were recently restated in a series of papers by Hedin and coworkers.[2] The relative strength of low energy excitations accompanying the “main line” photoemission spectrum is directly related to the dc resistivity and can be quite significant in materials of poor conductivity such as small-gap superconductors and semimetals.[3] We report angle resolved core-level photoemission spectra of the semimetals Sb and Bi where we observe a multiple peak structure separated by ~170-300 meV towards higher energy from the main 4d and 5d components, respectively.[4,5] Utilizing photons ranging from 30-150 eV, angular scans along the k-direction normal to the (111) surface and k || scans along high symmetry directions of the surface Brillouin-zone (SBZ), we find dispersion in the split-off components commensurate with the bulk and surface Brillouinzone periodicity. Additionally, the peak width and intensity of the split-off peak oscillates between final state symmetry points. From the wealth of accumulated information, we dismiss an earlier claim by Patthey et al. assigning the additional feature in the Bi 5d spectra to a surface- shifted component.[6] Since the d 5/2 and d 3/2 components show the same features symmetry arguments rule out crystal-field effects as the source of the observed peak splitting. The data can be explained by a k-dependent loss function consisting of several characteristic direct and indirect low energy interband transitions excited in various parts of the bulk Brillouin zone. Acknowledgements The Synchrotron Radiation Center (SRC) is funded by the National Science Foundation (NSF) under Grant No. DMR-0884402. References [1] J. N. Andersen, T. Balasubramanian, C.-O. Almbladh, et al., Physical Review Letters 86, 4398 (2001). [2] L. Hedin and J. D. Lee, Physical Review B 64, 115109 (2001).
Page 2 and 3: Welcome to the 36 th SRC Users’ M
Page 4 and 5: 12:20 - 1:10 Lunch 1:10 -1:45 Poste
Page 6 and 7: Administration Executive Director D
Page 8 and 9: STATUS OF THE SRC BEAMLINES AND INS
Page 10 and 11: ACCELERATOR DEVELOPMENTS Ken Jacobs
Page 12 and 13: HIGH ENERGY RESEARCH POSSIBILITIES
Page 14 and 15: ATOMICALLY UNIFORM THIN FILMS ON SI
Page 16 and 17: calculated binding energies of the
Page 18 and 19: MANY-ELECTRON EFFECTS ON THE XE 5S
Page 20 and 21: PHOTOELECTRON SPECTROMETRY OF ATOMI
Page 22 and 23: PHOTOEMISSION STUDY OF USb AND UTe
Page 24 and 25: CANADIAN SYNCHROTRON RADIATION FACI
Page 26 and 27: SELF-ASSEMBLY OF BLOCK COPOLYMERS O
Page 28 and 29: A B S T R A C T S
Page 30 and 31: Photoemission spectra, a.u. -0.3 -0
Page 32 and 33: THE INITIAL AND FINAL STATE BANDS I
Page 34 and 35: TRANSITION LAYERS AT BURIED FERROMA
Page 36 and 37: LOW-DIMENSIONAL ELECTRONS AT SILICO
Page 38 and 39: SUBCELLULAR DISTRIBUTION OF MOTEXAF
Page 40 and 41: LINEAR POLARIZATION MEASUREMENTS OF
Page 42 and 43: Fig.1: Photoemission spectra of opt
Page 44 and 45: The sample manipulator has a cool d
Page 46 and 47: Cr and Fe but for these U systems t
Page 48 and 49: [4] G. -H. Gweon, J. W. Allen, and
Page 52 and 53: [3] D. L. Mills, Physical Review B
Page 54 and 55: CHARACTERIZATION OF SULPHATE INTERA
Page 56 and 57: in the data acquisition chamber. Th
Page 58 and 59: spatially resolved chemistry of the
Page 60 and 61: THE RELATIONSHIP BETWEEN PHOSPHATE
Page 62 and 63: PHOTOEMISSION STUDIES OF QUANTUM WE
Page 64 and 65: Ag surface state such that it moves
Page 66 and 67: HIGH-RESOLUTION STUDY OF THE LITHIU
Page 68 and 69: RELATIVE PARTIAL CROSS SECTIONS AND
Page 70 and 71: Christian Ast Max-Planck Institute
Page 72 and 73: David L. Huber Physical Sciences La
Page 74 and 75: Tom Miller University of Illinois a
Page 76 and 77: Eric Wiedemann University of Wiscon
Page 78 and 79: Pete Hagen Phone: (608) 877-2154 Em
Page 80: NOTES

SRC Users' Meeting - Synchrotron Radiation Center - University of ...

You also want an ePaper? Increase the reach of your titles

Delete template?

Save as template?