Adaptable material

Metamaterials are often narrowband, but at least with this scheme one could adapt the material to new frequencies," says Ulf Leonhardt, a metamaterial researcher at the University of St Andrews in the UK.

That removes an obstacle to the wider use of metamaterial antennas. Such antennas would be attractive because they could help to shrink the size of cellphones.

Because metamaterials can manipulate electromagnetic waves to a greater degree than normal materials – and even bend light "backwards" – a small metamaterial antenna is as effective as a much larger standard antenna at transmitting or receiving waves.

But a narrowband metamaterial antenna has its drawbacks – it's rare that engineers require an antenna tuned to just one frequency, says Driscoll. For instance, different countries have allocated different frequency bands to their cellphone networks.

He says a tunable metamaterial antenna would allow a wireless gadget to work "outstandingly well" at the frequencies used in one country, but also carry the option of retuning for use abroad.