Regensburg 2013 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
O: Fachverband Oberflächenphysik
O 22: Nanostructures at Surfaces II
O 22.7: Vortrag
Montag, 11. März 2013, 17:30–17:45, H45
Structural Phase Transition on Si(553)-Au: Temperature and Tunneling Current Dependence — •Stefan Polei1, Ingo Barke1, Paul Snijders2, and Karl-Heinz Meiwes-Broer1 — 1Institut für Physik, Universität Rostock, Rostock, Germany — 2Materials Science & Technology Division, Oak Ridge Nat. Lab., Oak Ridge, Tennessee, USA
Atomic chains on semiconductor surfaces have gained considerable interest in the last few years because they are a promising model system for low dimensional physics. On Si(553)-Au earlier studies revealed competing periodicities of 1x2 and 1x3 unit cells [1]. Recently, the frequently observed 1x3 structure was attributed to a spin-polarized ground state with antiferromagnetic ordering [2]. In this contribution we present Scanning Tunneling Microscopy (STM) measurements of the Si(553)-Au surface at various temperatures and tunneling conditions. The periodicity of the Si step-edge chain is found to change gradually from 1x3 to 1x2 depending on temperature and magnitude of the tunneling current. As a consequence, the STM topography shows an apparent 1x6 structure in the transition regime. A Fourier-based analysis of the observed periodicities allows the deduction of a qualitative phase diagram as a function of current and temperature.
[1] P. C. Snijders et al., PRL 96, 076801 (2006); [2] S. C. Erwin, F. J. Himpsel, Nat. Commun. 1, 58 (2010)