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Ag surface state such that it moves above the Fermi level and becomes depopulated and significantly less intense [2]. Figure 2 shows the in-plane dispersion of the quantum well states and the surface state along the - K direction for a 22 ML thick Ag film. The bottom of the Ag surface state band is 26 meV above the Fermi level. A fit Figure1 Figure2 7.5 hv=22eV Ag on Au/Si- root3 0.0 Ag 22Ml Au/Si n=1 7.0 -0.2 Photoemission Intensity (arb.units) 6.5 6.0 5.5 Ag ML 22 19 16 14 12 Initial state energy (eV) -0.4 -0.6 -0.8 -1.0 n=2 n=3 5.0 10 8 -1.2 n=4 -3 -2 -1 0 Initial state energy (eV) 6 -1.4 -0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 k || (A -1 ) to the data (solid curve) reveals the effective mass m*/m of the surface state band to be 0.404 which is very close to the value 0.397 measured by F. Reinert et al [3] from the (111) surface of bulk Ag. The dispersions of the quantum well states (crosses) can be compared with those of Ag bulk bands calculated at constant k (triangles) [4]. The match between the measurement and calculation is good for the quantum-well states with quantum numbers n from n = 2 to n = 4. For the quantum-well state with n = 1, the dispersion is significantly less than that of the other quantum well states and corresponding calculated bulk value. We note that the deeper quantumwell states overlap the bulk bands in the substrate and so are really resonances; for such states the reflection phase shift at the interface is relatively slowly-varying and so the dispersions in Fig. 2 are approximately at constant k . In contrast, the energy of the n = 1 state is within the energy gap of the substrate, where the interface phase shift is rapidly varying. In this case, the dispersion in Fig. 2 includes an implicit variation in k so that the curvature may not reflect the true effective mass. Further analysis of the dispersions and effective masses of quantum well states from different other coverages will be done. This work is supported by the U.S. National Science Foundation (grant DMR-02-03003). We acknowledge the Petroleum Research Fund, administered by the American Chemical Society, and the U.S. Department of Energy, Division of Materials Sciences (grant DEFG02- 91ER45439), for partial support of the synchrotron beamline operation and the central facilities of the Frederick Seitz Materials Research Laboratory. The Synchrotron Radiation Center of the
University of Wisconsin-Madison is supported by the U.S. National Science Foundation (grant DMR-00-84402.). References: 1. H. M. Zhang, K. Sakamoto, and R. I. G. Uhrberg, Phys. Rev. B64, 245421 (2001). 2. G. Neuhold and K. Horn, Phys. Rev. Lett. 78, 1327 (1997). 3. F. Reinert, G. Nicolay, S. Schmidt, D. Ehm, and S. Hüfner, Phys. Rev. B63, 115415 (2001). 4. N. V. Smith and L. F. Matheiss, Phys. Rev. B 9, 1341 (1974); N. V. Smith, Phys. Rev. B 9, 1365 (1974)
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Welcome to the 36 th SRC Users’ M
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12:20 - 1:10 Lunch 1:10 -1:45 Poste
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Administration Executive Director D
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STATUS OF THE SRC BEAMLINES AND INS
Page 10 and 11:
ACCELERATOR DEVELOPMENTS Ken Jacobs
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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 50 and 51: References [1] S. Cho, Y. Kim, A. D
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 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
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