Imagine a future where your contact lenses gave you Predator vision. One day, it might happen, thanks to graphene.
Researchers at the University of Michigan have developed the first room-temperature light detector that can see the entire infrared spectrum of colours. And it can be small and compact, because graphene is insane and only one atom thick. Before now, however, it hadn’t been a viable tool for detecting infrared light because it’s so thin and can’t pick up the electrical signal of that type of light wavelength. But U Michigan’s crack team of researchers developed a new way of picking up these signals. Phys.org explains:
To make the device, they put an insulating barrier layer between two graphene sheets. The bottom layer had a current running through it. When light hit the top layer, it freed electrons, creating positively charged holes. Then, the electrons used a quantum mechanical trick to slip through the barrier and into the bottom layer of graphene. The positively charged holes, left behind in the top layer, produced an electric field that affected the flow of electricity through the bottom layer. By measuring the change in current, the team could deduce the brightness of the light hitting the graphene. The new approach allowed the sensitivity of a room-temperature graphene device to compete with that of cooled mid-infrared detectors for the first time.
The takeaway is that the pinky fingernail-sized device could one day find its way into your contact lenses, giving you heat vision at will. Yes, this is a very pie-in-the-sky idea that will likely never actually happen. Then again, that’s what they said about a team of elite commandos taking on a dreadlocked alien hunter deep in the Val Verde rainforest. [Nature via Phys.org]