Physicists have designed a 2D device that can emit bright, visible light, paving the way for ultra-thin light-emitting devices.

One-atom-thick layers of carbon called graphene can withstand the high temperatures at which they emit light. But when graphene is stuck to a surface and electricity is applied, only a small amount of light energy is released because too much energy dissipates as heat. Young Duck Kim at Seoul National University and his colleagues got around the problem by putting a current through a piece of graphene suspended between two electrodes in a vacuum. By isolating the graphene, they were able to heat it to more than 2,500 °C and increase the level of radiation by 1,000 times compared to graphene on a substrate.

With further improvements, the device could serve as a nanoscale light emitter in ultra-thin displays, say the authors.

Nature Nanotech. http://dx.doi.org/10.1038/nnano.2015.118 (2015)