Imagine electrical circuits that you could print off and use for a few hours before they melted away and stop functioning or changed their function. A spy's best friend, they could become reality thanks to a new kind of electric circuitry printed on graphene.
The idea of electrical components that self-destruct is nothing new. We've all watched Mission Impossible and Xerox has already developed a chip that self-destructs. But the new technique from the Georgia Institute of Technology instead creates an electrical circuit that's deposited onto a sheet of graphene, which then melts into the structure of the carbon sheets over time.
What the researchers have in fact done is use an electron microscope to deposit carbon atoms on top of a sheet of graphene. Sat there, they create a small electrical circuit. But over time, the electrical properties get chewed up by the graphene itself, leaving no circuit to be seen at all. Or, alternatively, the circuits can be drawn so that they can change over time, rather than disappearing entirely. Andrei Fedorov, one of the researchers, explains to PhysOrg:
"You could design a circuit that operates one way now, but after waiting a day for the carbon to diffuse over the graphene surface, you would no longer have an electronic device. Today the device would do one thing; tomorrow it would do something entirely different."
How the circuitry changes over time can be influence by the way the carbon atoms are added in the first place -- barriers can be added to influence the way the atoms move, for instance, or some atoms fused in place permanently by the addition of laser light -- while the rate of change relies on temperature. The research is published in Nanoscale.
Now, the researchers plan to use the technique to build a modular set of different 'devices' that can be used together and tuned to change at different rates, to create reconfiguring or disappearing circuits.