Published in Phys. Rev. Lett. 106, 067601 (2011).

Co-existence of negatively and positively buckled isomers on n⁺ doped Si(111)-2x1

G.Bussetti,¹ B.Bonanni,¹ S.Cirilli,¹ A.Violante,¹ M.Russo,¹ C.Goletti,¹ P.Chiaradia,¹ O.Pulci,² M.Palummo,² R.Del Sole,² P.Gargiani,³ M.G. Betti,³ C. Mariani,³ R.M. Feenstra,⁴ G. Meyer,⁵ and K.H. Rieder⁶
¹Dipartimento di Fisica, NAST and CNISM, Università di Roma ‘Tor Vergata’, via della Ricerca Scientifica 1, 00133 Roma, Italy
²Dipartimento di Fisica, NAST, ETSF and MIFP, Università di Roma ‘Tor Vergata’, via della Ricerca Scientifica 1, 00133 Roma, Italy
³Dipartimento di Fisica and CNISM, Università di Roma, ‘La Sapienza’, Roma, Italy
⁴Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA
⁵IBM Research Division, Zurich Research Laboratory, 8803 Rüschlikon, Switzerland
⁶Department of Chemical Physics, Fritz Haber Institute of the Max Planck Society, Faradayweg 4-6, D-14195 Berlin, Germany

Abstract

A long-standing puzzle regarding the Si(111)-2x1 surface has been solved. The surface energy gap previously determined by photoemission on heavily n-doped crystals was not compatible with a strongly bound exciton known from other considerations to exist. New low-temperature angleresolved photoemission and scanning tunneling microscopy data, together with theory, unambiguously reveal that isomers with opposite bucklings and different energy gaps co-exist on such surfaces. The subtle energetics between the isomers, dependent on doping, leads to a reconciliation of all previous results.

Click here for preprint of paper, in pdf format.

Return to Home Page of Feenstra group

Co-existence of negatively and positively buckled isomers on n+ doped Si(111)-2x1

Abstract

Co-existence of negatively and positively buckled isomers on n⁺ doped Si(111)-2x1