The more the researchers narrowed their focus, the clearer the patterns became, so they zeroed in even further, reducing the area the microscope scanned until they were looking at only one ripple at a time. Eventually, they tried something new: pausing the scan and simply taking measurements from a single spot, “like looking at a buoy which only moves up and down in the ocean,” Thibado explained. This was a novel use of STM and marked the turning point in their research.

When Thibado’s team analyzed the “point mode” data, they could observe two distinct features: small Brownian motion and larger, coordinated movements. In these larger movements, the entire ripple buckled, flipping up and down like a thin piece of metal being repeatedly flexed.

The pattern of small random motion combined with larger sudden movements is known as Lévy flights. This phenomenon can be observed in a variety of contexts, such as biomedical signals, climate dynamics, the behavior of foraging animals, and even the movement of crowds at Disney World. Thibado is the first to have observed these flights spontaneously occurring in an inorganic atomic-scale system. His team published these results in the journal Physical Review Letters.

An Energy Breakthrough

Other researchers have theorized that temperature-induced curvature inversion in graphene could be used as an energy source, and even predicted the amount of energy they could produce. What sets Thibado’s work apart is his discovery that graphene has naturally occurring ripples that invert their curvature as the atoms vibrate in response to the ambient temperature.

“This is the key to using the motion of 2D materials as a source of harvestable energy,” Thibado said. Unlike atoms in a liquid, which move in a random directions, atoms connected in a sheet of graphene move together. This means their energy can be collected using existing nanotechnology.

Thibado has taken the first steps toward creating a device that can turn this energy into electricity, with the potential for many applications. He has been awarded a provisional patent on this invention, called a Vibration Energy Harvester, or VEH.

Such a device would involve a negatively charged sheet of graphene suspended between two metal electrodes. When the graphene flips up, it induces a positive charge in the top electrode, and when it flips down, it charges the bottom one, creating an alternating current.