Valence band structure of the icosahedral Ag-In-Yb quasicrystal

Journal Article · Mon Mar 01 00:00:00 EST 2010 · Physical Review. B, Condensed Matter and Materials Physics

DOI:https://doi.org/10.1103/PHYSREVB.81.104205· OSTI ID:21366697

Sharma, H R; Simutis, G; Dhanak, V R; Nugent, P J; McGrath, R ^[1]; Cui, C ^[2]; Shimoda, M ^[3]; Tsai, A P ^[2]; Ishii, Y ^[4]

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1. Surface Science Research Centre and Department of Physics, University of Liverpool, Liverpool L69 3BX (United Kingdom)
2. Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577 (Japan)
3. National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan)
4. Department of Physics, Chuo University, Kasuga, Tokyo 112-8551 (Japan)

The valence band structure of the icosahedral (i) Ag-In-Yb quasicrystal, which is isostructural to the binary i-Cd-Yb system, is investigated by ultraviolet photoemission spectroscopy (UPS). Experimental results are compared with electronic-structure calculations of a cubic approximant of the same phase. UPS spectra from the fivefold, threefold, and twofold i-Ag-In-Yb surfaces reveal that the valence band near to the Fermi level is dominated by Yb 4f-derived states, in agreement with calculations. The spectra also exhibit peaks which are surface core level shifted, caused by changes in the electronic structure in surface layers. Calculations yield a pseudogap in the density of states due to a hybridization of the Yb 5d band with the Ag 5p and In 5p bands. Both experimental and calculated band features are very similar to those of Cd-Yb. The modification of the band structure after surface treatment by sputtering and by oxidation is also studied. Additionally, the work function of i-Ag-In-Yb measured from the width of UPS spectrum is found to be almost unaffected by surface orientation, but increases after sputtering or oxidation.

• OSTI ID: 21366697
• Journal Information: Physical Review. B, Condensed Matter and Materials Physics, Vol. 81, Issue 10; Other Information: DOI: 10.1103/PhysRevB.81.104205; (c) 2010 The American Physical Society; ISSN 1098-0121
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CRYSTALS
DENSITY
ELECTRONIC STRUCTURE
FERMI LEVEL
INDIUM COMPOUNDS
LAYERS
MODIFICATIONS
ORIENTATION
OXIDATION
PHOTOEMISSION
SILVER COMPOUNDS
SIMULATION
SPECTRA
SPECTROSCOPY
SPUTTERING
SURFACE TREATMENTS
SURFACES
ULTRAVIOLET RADIATION
VALENCE
WORK FUNCTIONS
YTTERBIUM COMPOUNDS
CHEMICAL REACTIONS
ELECTROMAGNETIC RADIATION
EMISSION
ENERGY LEVELS
FUNCTIONS
PHYSICAL PROPERTIES
RADIATIONS
RARE EARTH COMPOUNDS
SECONDARY EMISSION
TRANSITION ELEMENT COMPOUNDS