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Controlled Contact to a C60 Molecule

N. Neel·J. Kroger·L. Limot·T. Frederiksen·M. Brandbyge·R. Berndt
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Abstract

The conductance of C60 on Cu(100) is investigated with a low-temperature scanning tunneling microscope. At the transition from tunneling to the contact regime the conductance of C60 adsorbed with a pentagon-hexagon bond rises rapidly to 0.25 conductance quanta G0. An abrupt conductance jump to G0 is observed upon further decreasing the distance between the instrument's tip and the surface. Ab-initio calculations within density functional theory and non-equilibrium Green's function techniques explain the experimental data in terms of the conductance of an essentially undeformed C60. From a detailed analysis of the crossover from tunneling to contact we conclude that the conductance in this region is strongly affected by structural fluctuations which modulate the tip-molecule distance.

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N. Neel, J. Kroger, L. Limot, T. Frederiksen, M. Brandbyge, R. Berndt. 2006-08-22. Controlled Contact to a C60 Molecule. https://doi.org/10.1103/physrevlett.98.065502

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