Substrate-induced array of quantum dots in a single-walled carbon nanotube

Single-walled carbon nanotubes are model one-dimensional structures. They can also be made into zero-dimensional structures; quantum wells can be created in nanotubes by inserting metallofullerenes, by mechanical cutting or by the application of mechanical strain. Here, we report that quantum dot arrays can be produced inside nanotubes simply by causing a misalignment between the nanotube and the <100> direction of a supporting silver substrate. This method does not require chemical or physical treatment of either the substrate or the nanotube. A short quantum dot confinement length of 6 nm results in large energy splittings.