Electrons jump impossible gaps in graphene, filmed
Published
Physicists have watched electrons leap across energy gaps in graphene that they normally cannot occupy. A team from the University of Regensburg, Philipps-Universität Marburg and Forschungszentrum Jülich tracked the jumps, according to a Forschungszentrum Jülich release on ScienceDaily. The findings are published in Nature.
In a solid, electrons normally stay inside certain energy bands, with forbidden gaps between them. The team hit graphene, a sheet of carbon atoms, with intense pulses of light. The electric field of the light pushed some electrons straight across a gap into the next band. These jumps are called Landau-Zener-Majorana transitions.
Physicists had suspected the effect matters for fast semiconductor electronics, but had never seen it unfold directly. The team used a new kind of slow-motion electron camera to follow the movement. The release says some of the transitions happen with a 100 percent probability.
Why it matters: the release says the work could help build ultrafast electronics switched by light. That is a hope for later, not a product. Other labs will need to repeat the measurements before the result is widely accepted.
Easy question: would you expect light-driven chips to reach phones within ten years?
Sources: ScienceDaily