Such miniturisation technologies have great potential in a range of fields including medical diagnostics and new electronic devices

The story continues “….most touch screens and solar panels are glass-based. The hard, insulating glass helps protect and support the thin coating of electrically conductive metals. But glass is also brittle and heavy. When an object strikes a solar panel, or a person drops a cell phone, the glass can shatter. Touch screens made from thin plastic coated with silver and gold would weigh less, take up less volume, be more flexible and could be produced much more quickly than glass plates.”

What the story doesn’t mention is that one of the major problems with current touch screen technology concerns the use of indium tin oxide (ITO) for the conductive transparent layer. At current levels of mine production and consumption, some analysts predict that there is only 15 years supply of indium left.

A team at the Electronics and Telecommunications Research Institute in Daejeon, South Korea, recently transferred data between computer chips using plasmons to channel a broadband light signal along gold wires. Some manufacturers, including Intel, are beginning to use connections of this type to replace conventional wiring in personal computers.

The ultimate aim, though, is to have light itself perform the processing in every microchip. Part of the trick here lies in the ability to generate pulses of light and switch them on and off at high speed, all in a tiny space. The smallest conventional lasers measure several hundred nanometres across and so are simply too big for the task. To compete with transistors, a laser would need to be less than 50 nanometres across, an impossibility with conventional designs.

Then last year teams of physicists in the US and China created the first examples of a device known as a spaser, which gets its name from the fact that it amplifies surface plasmons in a similar way to how a laser boosts light. The spaser has a gold core wrapped in silica and dye molecules. When it is switched on – using an external light source at present, though the goal is to use an electric current – the gold core ripples with plasmons. These excite the dye molecules, which emit light. This light in turn creates more plasmons. The result is a beam of light from a device tens of nanometres wide.

This concept was highlighted in the white paper WGC published a few months ago.

“The use of gold nanoparticles could be an essential step towards the mainstream adoption of organic electronics, as they are commercially readily available and do not oxidise or rust, unlike other nanoparticles which have been tested, such as iron. Conventional electronics have manufacturing steps at very high temperatures – sometimes up to 1,000oC, or greater – and these processes are extremely energy intensive and therefore expensive. Organic materials can be processed at room temperature and so require considerably less energy. It also means they can be used with cheap and flexible plastic substrates, which would melt in conventional silicon, high-temperature processing steps.”