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Cr and Fe but for these U systems the band widths and dispersions are two orders of magnitude smaller. Work Supported by the US Department of Energy, Office of Science. The SRC is operated under Grant No. DMR-0084402.
Hidden One Dimensionality and Non-Fermi Liquid ARPES Lineshapes of the Electronic Structure of η-Mo 4 O 11 G. –H. Gweon 1* , S. –K. Mo 1 , J. W. Allen 1 , H. Höchst 2 , J. L. Sarrao 3 , and Z. Fisk 3 1. Randall Laboratory of Physics, University of Michigan, Ann Arbor, MI 48109 2. Synchrotron Radiation Center, University of Wisconsin, Stoughton, WI 53589 3. National High Magnetic Field Lab., Florida State University, Tallahassee, FL 32306 η-Mo 4 O 11 is a layered metal that undergoes two charge density wave (CDW) transitions at 109 K and 30 K, and is unique in showing a bulk quantum Hall effect [1]. Research so far indicates that this material has a “hidden one-dimensional” (hidden-1d) Fermi surface (FS) in the normal state (T > 109 K), whose nesting property drives the 109 K CDW formation [2]. Here, we directly confirm this picture by angle resolved photoemission spectroscopy (ARPES). Figure 1 shows the Fermi energy intensity map measured at T=150K and with hν=17eV at the 4m-NIM line of the Synchrotron Radiation Center. The geometry of the FS is in good general agreement with that of the band calculation, and can be seen as two vertical lines of hidden-1d FS coming from chains along the crystal b axis and double oblique hidden 1-d lines coming from chains along the crystal (b±c) axes. The latter are characterized by a single nesting vector Q CDW , similar to the situation of other 2-d hidden-1d materials like NaMo 6 O 17 and KMo 6 O 17 [3]. Fig 2 shows the temperature dependent change of the valence band spectrum at point A and B respectively. We have observed that there is a small gap opening of size ~15meV only at the point A accompanied with a change in the line shape, while at the point B, which is a part of the remnant FS that is not nested by Q CDW, the spectrum does not show any change as the temperature decreases. Even more interesting, this material also shows the same ARPES line shape anomalies and lack of Fermi edge in the angle integrated spectrum, that we have identified in other low dimensional metals and that are most easily rationalized within an electron fractionalization scenario that includes for the quasi-2d systems the idea of a “melted holon” part of the lineshape, arising from disorder [4]. This lineshape is neatly confined to the electronic bandwidth but is essentially featureless in energy and k. It is best seen in a region of k-space where all dispersing peaks lie above the Fermi energy. Fig. 3 shows the “melted holon” lineshape of η-Mo 4 O 11 obtained at such a point in k-space, along the yellow line marked in the Fig. 1. Disorder that could be responsible is known in this material [5]. More detailed studies on the lineshapes and also of the 30 K CDW transition are in progress. The work at University of Michigan is supported by the US NSF grant No. DMR-0302825. The SRC is supported by the US NSF grant No. DMR-00-84402. References [1] S. Hill et al., Phys. Rev. B 58, 10778 (1998). [2] E. Canadell et al., Inorganic Chemistry 28, 1466 (1989) [3] G. –H. Gweon et al., Phys. Rev. B 55, R14453 (1997). * current address: Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
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 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 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

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