Regensburg 2004 – wissenschaftliches Programm
O 11.4: Vortrag
Montag, 8. März 2004, 16:30–16:45, H44
The electronic structure of Pb films on Si(111) — •Ad Ettema1, Anton Mans1, Hugo Dil2, JeongWon Kim2, and Karsten Horn2 — 1TUDelft (NL) — 2Fritz Haber Institute, Berlin
The Pb/Si(111) system shows a rich variety of interesting physical properties and phenomena, such as the magic height of islands, vertical Friedel oscillations  , a competition between classical and quantum mechanical effects in the shape relaxation , anomalous optical absorption  and anomalous behaviour in the Hall effect as a function of thickness.
In this contribution we present the results of photoemission experiments carried out at the synchrotron radiation facilities of MAX-lab in Lund (Sweden) and BESSY in Berlin. The results show an anomalously large in-plane effective mass of the 2D quantum well state bands, whereas the original bulk band has a strong dispersion and a free electron behaviour. Moreover, band structure calculations for bulk and thin film slabs predict bands with predominantly free electron character. Our analysis suggests that this phenomenon may be due to a strong electron correlation effect in the 2D bands of the Pb quantum well states.
 W.B. Jian, W.B. Su, C.S. Chang and T.T.Tsong, Physical Review Letters 90, 6603 (2003).  H Okamoto, D. Chen, T. Yamada , Physical Review Letters 89, 6101 (2002). M Jalochowski et al, Physical Review B 66, 205417 (2002).