Conductance of carbon nanocapsule junctions

Carbon nanocapsules were manipulated inside a high-resolution transmission electron microscope and assembled into single-nanocapsule junctions sandwiching between two gold electrodes. The electric conductivity was measured simultaneously with the lattice imaging of structural dynamics. It was found that the differential conductance of the junction at bias voltages from 0 to 0.20 V corresponded to half of quantized conductances, i.e., 0.5G(0) where G(0) = 2e(2)/h is the conductance quantum, e is the electron charge, and h is Planck's constant. At bias voltages larger than 0.20 V, the interface structure between the capsule and the electrode changed and the differential conductance increased to 1G(0). The study showed that carbon nanocapsule junctions are quantized conductors.