Entanglement is a feature of quantum mechanics that allows particles to share a much closer relationship than classical physics permits. A measurement on one part of an entangled system reveals the properties of the other part, even if they are physically separated.

One source of entangled electrons is the Cooper pairs that exist in gapped BCS superconductors. For quantum information technology to take off, scientists must find a way to separate these electrons and transport them over long distances.

The UCSB team showed how entangled pairs from a superconductor could be injected into two single-walled metallic carbon nanotubes. The nanotubes would also be able to transport the entangled states over "appreciable distances".

The scientists report their work in the 15 July issue of Physical Review Letters.