Electronic switching is the key to powering everything from your alarm clock to the world's fastest supercomputers, and now scientists believe they've captured this switching in action in an electronic device.
Researchers published a new paper this week in the journal Science describing how they used a specialized, ultrafast camera capable of seeing things at the atomic scale to take pictures of an electronic switch as they sent electric pulses to it.
Then, they strung these pictures together into a kind of gif or movie that showed how the atomic structure of the switch changed as electric pulses were applied, switching it from an insulating state to a conductive state.
"This research is a breakthrough in ultrafast technology and science," said Xijie Wang, a SLAC National Accelerator Laboratory (SLAC) scientist and co-author of the paper. "It marks the first time that researchers used ultrafast electron diffraction, which can detect tiny atomic movements in a material by scattering a powerful beam of electrons off a sample, to observe an electronic device as it operates."
Capturing the electronic switching cycle
The research team built custom miniaturized switches made of vanadium dioxide, an important material with the ability to change between insulating and conductive states near room temperature that makes it ideal for future computer development.
They then used electric pulses to trigger the switch between states while using SLAC's ultrafast electron diffraction camera, MeV-UED, to image the arrangement of the switch's atoms over just billionths of a second.
"This ultrafast camera can actually look inside a material and take snapshots of how its atoms move in response to a sharp pulse of electrical excitation," said Aaron Lindenberg, a professor in the Department of Materials Science and Engineering at Stanford University and an investigator with the Stanford Institute for Materials and Energy Sciences (SIMES) at SLAC. "At the same time, it also measures how the electronic properties of that material change over time."
Capturing the motion of atoms in this way will hopefully give scientists a better understanding of how these electronic switches work, and should help computer engineers in the years ahead build better electronics that have greater durability and efficiency.