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Spatially resolved manipulation of single electrons in quantum dots using a scanned probe

A. Pioda·S. Kicin·T. Ihn·M. Sigrist·A. Fuhrer·K. Ensslin·A. Weichselbaum·S. E. Ulloa·M. Reinwald·W. Wegscheider
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Abstract

The scanning metallic tip of a scanning force microscope was coupled capacitively to electrons confined in a lithographically defined gate-tunable quantum dot at a temperature of 300 mK. Single electrons were made to hop on or off the dot by moving the tip or by changing the tip bias voltage owing to the Coulomb-blockade effect. Spatial images of conductance resonances map the interaction potential between the tip and individual electronic quantum dot states. Under certain conditions this interaction is found to contain a tip-voltage induced and a tip-voltage independent contribution.

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A. Pioda, S. Kicin, T. Ihn, M. Sigrist, A. Fuhrer, K. Ensslin, A. Weichselbaum, S. E. Ulloa, M. Reinwald, W. Wegscheider. 2004-11-10. Spatially resolved manipulation of single electrons in quantum dots using a scanned probe. https://doi.org/10.1103/physrevlett.93.216801

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