Reversing the Casimir Effect

The Casimir effect or Casimir-Polder force is a physical force exerted between separate but extremely close objects and can be dominant on the nano scale, the strength of the force falling off rapidly with distance. It poses significant problems for nanotechnologists.

Using a special lens of a kind that has already been built, Prof Ulf Leonhardt and Dr Thomas Philbin report in the New Journal of Physics they can engineer the Casimir force to repel, rather than attract. Because the Casimir force could potentially cause problems for nanotechnologists, who are trying to build electrical circuits and tiny mechanical devices on silicon chips, among other things, the team believes the feat could initially be used to stop tiny objects from sticking to each other.

See Daily Telegraph.
Also Wikipedia - The Casimir Effect.