Structural and electronic properties of Au induced nanowires on Ge(001)

The structural and electronic properties of Au induced self-organized nanowires on Ge(001), prepared by different procedures, are investigated with scanning tunnelling microscopy and spectroscopy at room temperature and 77 K. We find that the Au induced nanostructures are identical for the different preparation procedures. The Au induced nanowires are comprised of dimers that have their bond aligned in a direction perpendicular to the nanowire. The dimers are buckled, leading to a 2× periodicity along the nanowires. Dimers located at antiphase boundaries are dynamic and flip back and forth between two buckled configurations. The troughs between the nanowires have a depth of several atomic layers. Finally, the differential conductivities of the nanowires and the troughs are very comparable in magnitude.