Si atom wire growth for quantum information processing

We report on the experimental realization of straight atomic wires of Si on a vicinal Si(111) substrate. Atomic-kink-free steps with an identical structure are formed on the clean substrate by prolonged annealing around 800 °C. The direction of the annealing DC current that is effective to extend the straight step region is the so-called kink-up direction. Furthermore, the step-edge structure obtained is serendipitously suitable for the exclusive growth of the single adatom wires by molecular beam epitaxy. An isotopic version of such a structure is expected to be the most basic building block for a silicon-based quantum computer.