Vertical atom manipulation on a III-V semiconductor surface

Starting with the pioneering research of Eigler et al. in the early 1990s, scanning tunneling microscopy at cryogenic temperatures made it possible to place single atoms at selected positions at a surface. Since then, STM-based manipulation has been applied mainly to atoms adsorbed on metal surfaces. We recently extended this technique to III-V semiconductor materials and demonstrated the reversible repositioning of native In adatoms on the InAs(111) - a surface grown by molecular beam epitaxy. This approach allows us to probe the electronic properties of individual quantum structures on a semiconductor platform in an atom-by-atom fashion.

Four In adatoms on InAs(111)A which were assembled by vertical atom manipulation to form a linear chain. The In adatoms reside on In-vacancy sites of the (2x2) surface reconstruction at an interatomic spacing is 8.57 Å.

Stefan Fölsch, Jianshu Yang, Christophe Nacci, Kiyoshi Kanisawa, Atom-by-atom quantum state control in adatom chains on a semiconductor, Phys. Rev. Lett. 103 (2009), 096104.