Scanning Quantum Dot Microscopy.

  title={Scanning Quantum Dot Microscopy.},
  author={Christian Wagner and Matthew F. B. Green and Philipp Leinen and Thorsten Deilmann and Peter Kr{\"u}ger and Michael Rohlfing and Ruslan Temirov and F. Stefan Tautz},
  journal={Physical review letters},
  volume={115 2},
We introduce a scanning probe technique that enables three-dimensional imaging of local electrostatic potential fields with subnanometer resolution. Registering single electron charging events of a molecular quantum dot attached to the tip of an atomic force microscope operated at 5 K, equipped with a qPlus tuning fork, we image the quadrupole field of a single molecule. To demonstrate quantitative measurements, we investigate the dipole field of a single metal adatom adsorbed on a metal… 

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