Ballistic transport of electrons through conductors whose width is comparable with the electron Fermi wavelength is quantized in units of the quantum of conductance G0. Using the tip of a cryogenic scanning tunnelling microscope we contact controllably and reproducibly single atoms and molecules adsorbed on metal surfaces. For noble and transition metal atoms we find a contact conductance of ~ G0. Intriguingly, C60 molecules exhibit conductances between ~ G0/5 and ~ G0/4 depending on their adsorption geometry on the surface. We further show that in contact with the tip, C60 orientations can be switched reversibly. Latest results address spin-polarized transport through magnetic atoms.
Ballistic transport of electrons through conductors whose width is comparable with the electron Fermi wavelength is quantized in units of the quantum of conductance G0. Using the tip of a cryogenic scanning tunnelling microscope we contact controllably and reproducibly single atoms and molecules adsorbed on metal surfaces. For noble and transition metal atoms we find a contact conductance of ~ G0. Intriguingly, C60 molecules exhibit conductances between ~ G0/5 and ~ G0/4 depending on their adsorption geometry on the surface. We further show that in contact with the tip, C60 orientations can be switched reversibly. Latest results address spin-polarized transport through magnetic atoms.
