A single molecule of carbon-60 bouncing between gold electrodes is the basis of a new transistor which has been developed by US scientists. The football-shaped carbon-60 molecule is called a fullerene or "buckyball" after architect Buckminster Fuller, and is formed by carbon atoms arranged in 12 pentagons and 20 hexagons.
The new transistor works by quantum tunnelling: electrons of the right energy can tunnel across the gap between the electrode and the buckyball to occupy the lowest energy level in the molecule; if the electron has additional energy that is equivalent to the vibration energy of the molecule, it can tunnel onto the molecule and set it in motion. Under the right conditions, the researchers believe one electron at a time can be transferred between the electrodes via the bouncing buckyball. Since the energy of vibration of the molecule is quantized, there is automatically a tight control on the current flowing through the transistor that could be exploited for accurate current measurement.