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arXiv · 1506.04618

Shifting the Voltage Drop in Electron Transport through a Single Molecule

Sujoy Karan·David Jacob·Michael Karolak·Christian Hamann·Yongfeng Wang·Alexander Weismann·Alexander I. Lichtenstein·Richard Berndt
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Abstract

A Mn-porphyrin was contacted on Au(111) in a low-temperature scanning tunneling microscope (STM). Differential conductance spectra show a zero-bias resonance that is due to an underscreened Kondo effect according to many-body calculations. When the Mn center is contacted by the STM tip, the spectrum appears to invert along the voltage axis. A drastic change in the electrostatic potential of the molecule involving a small geometric relaxation is found to cause this observation.

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Sujoy Karan, David Jacob, Michael Karolak, Christian Hamann, Yongfeng Wang, Alexander Weismann, Alexander I. Lichtenstein, Richard Berndt. 2015-06-16. Shifting the Voltage Drop in Electron Transport through a Single Molecule. https://doi.org/10.1103/physrevlett.115.016802

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