Initiating and monitoring the evolution of single electrons within atom-defined structures

Mohammad Rashidi, Wyatt Vine, Thomas Dienel, Lucian Livadaru, Taleana Huff, Jacob Retallick, Konrad Walus, Robert Wolkow

Published 2017-09-28Version 1

Scanning probe microscopes are frequently used to willfully position atoms or molecules in the design of artificial nanostructures. In principle, one could envision that these techniques could be extended to include the patterning and control of single electrons on the surface. To this end, the remarkable charge sensitivity of atomic force microscopes has been utilized to observe and control the charge states of atoms and molecules on the surface, however, studies thus far have relied upon techniques that apply large perturbative fields by the probe. By creating atomically precise structures via hydrogen lithography we in turn design novel charge structures, and by performing a series of field-free non-contact atomic force microscopy measurements with different tip heights we elucidate the interaction between the tip and the charge confined to these structures. We find that with small tip-sample separations the tip can be used to controllably position charge within the structures, i.e. write a given charge state. By increasing the tip-sample separation we can non-perturbatively read the charge states of these structures in a digital fashion. Combining these two interaction regimes we can efficiently prepare given charge states of atomically defined systems, and follow their field-free temporal evolution.