New research on infrared vision could pave the way to ultimately realizing science fiction’s fabled X-ray vision as a viable technology. A research team from the University of Buffalo has found a way to see through multiple layers of graphene sheets in order to identify the electronic properties of each one separately. To do so, an infrared light beam is shot at a stack to measure how the light wave’s direction changes while bouncing off each layer, even when they cover each other up.
“By measuring the polarization of reflected light from graphene in a magnetic field,” says John Cerne, PhD and University of Buffalo professor of physics, “we have developed an ultrasensitive fingerprinting tool that is capable of identifying and characterizing different graphene multilayers.” This method allows researchers to examine dozens of layers within a stack individually.
Graphene is a nanomaterial made up of a single layer of carbon atoms, and regarded as of the world’s strongest lightweight materials. Cerne’s research investigates the material’s electric properties, which change as sheets of the material are stacked on one another. Many different types of graphene exist, and when a magnetic field is applied to an infrared lazer, the direction of oscillation changes. A graphene layer stacked neatly on top of another will also have a different effect on the dispersal of light than one that is messily stacked.
No two stacks of graphene layers affect light polarization the same way. The reason for this lies in the fact that different layers absorb and emit light in different ways, and patterns change when a magnetic field is applied. Oscillation, also known as polarization, can be turned on and off by applying a magnetic field to graphene layers or–more quickly–by applying a voltage that sends electrons flowing through the graphene. Speaking about applying voltage, postdoctoral fellow at the Naval Research Laboratory, Chase T. Ellis, notes that this would “allow for fast modulation, which opens up the possibility for new optical devices using graphene for communications, imaging and signal processing.”
While we could see an great boon in telecommunication, imaging and signal processing, the ability of going through dozens of graphene stacks and analyzing them individually invites us to wonder about developing large-scale X-ray technologies. We could turn this technology to space or the deep ocean in order to access unseen layers and interpret what bounces back from infrared light beams. It could also be used to see and sort through entire floors of buildings and, in good hands, be beneficial for security purposes.
Photo Credit: Buffalo.edu