Modeling uncovers an ’atomic waltz’ for atom manipulation

Indirect exchange mechanism for the electron-beam manipulation of bismuth or antimony dopants in silicon based on computer simulations. The crimson sphere is a bismuth atom, while yellow and green spheres are respectively its nearest and next-nearest silicon neighbours. Toma Susi & Alexander Markevich / University of Vienna, Andrew R. Lupini) - Researchers at the University of Vienna's Faculty of Physics in collaboration with colleagues from the Oak Ridge National Laboratory in the USA have uncovered a non-destructive mechanism to manipulate donor impurities within silicon using focused electron irradiation. In this novel indirect exchange process not one but two neighbouring silicon atoms are involved in a coordinated atomic "waltz", which may open a path for the fabrication of solid-state qubits. The results have been published in the Journal of Physical Chemistry. Engineering materials at the atomic scale is an ultimate goal of nanotechnology. Well-known examples of atom manipulation with scanning tunneling microscopy range from the construction of quantum corals to rewritable atomic memories.