Originally developed for use in molecular electronics and memory, cross-bar architectures could also have applications in nano devices such as optoelectronic components and biological and chemical sensors. The UCLA researchers' design consists of two sets of wires, each aligned perpendicularly to the other. Individually addressable switches sit at the intersections of the wires: they are controlled by the electric input to each arm of the crossbar.

"By linking molecular switches and wires, we created highly effective logic gates with true molecular dimensions," said James Heath, professor of chemistry at UCLA and a scientific co-founder of Nanosys. "This architecture can easily circumvent chemical imperfections: if an individual switch is defective, the electric signal can still reach its destination via parallel wires."

Heath's lab has created working 16-bit memory circuits using the technology and aims to have working prototypes of a range of nano-based devices "within a few years". What's more, Heath claims that assembling wires and switches into the cross-bar pattern is simple and reproducible, so that the process can be scaled up for large-volume manufacturing.