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One-dimensional versus two-dimensional surface states on stepped Au(111)

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2002-04-15
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American Physical Society
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Surface states at vicinal Au(788) and Au(322) have been investigated with angle-resolved photoemission and synchrotron radiation. Both surfaces are characterized by highly regular one-dimensional step arrays with relatively wide (similar to3.9 Angstrom) or narrow (similar to1.3 Angstrom) terraces in Au(788) and Au(322), respectively. Depending on the terrace size we observe that surface electrons behave in a completely different way. In Au(788) terraces become one-dimensional, lateral quantum wells that confine surface electrons between adjacent steps. In Au(322) surface electrons propagate across the step array forming two-dimensional superlattice bands. By tuning photon energy and angle we probe fundamental properties of the electron wave functions in both cases.
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© 2002 The American Physical Society. A.Mu. and J.E.O. are supported by the Universidad del País Vasco (1/UPV/EHU/00057.240-EA-8078/2000). V.R. and S.R. are supported by the CNRS-ULTIMATECH program, the CRIF and the Université de Paris 7. V. P.-D. is supported by the Comunidad Autónoma de Madrid (Project No. 07N/0042/98) and the DGICYT (Spain) (Grant No. PB-97-119). The experiments performed at LURE were funded by the Large Scale Facilities program of the European Union. Critical reading of the manuscript by F. J. Himpsel and F. J. García de Abajo is acknowledged. Technical support from the Spanish-French beam line staff is gratefully acknowledged
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