Capturing Atom Movements in Real Time Produce Better Material Design

Researchers utilized an MRI-like technique to track the movement of individual atoms in real-time as they group together to form two-dimensional materials with a thickness of a single atomic layer.

Study findings (Following atoms in real-time could lead to better materials design) can be used in crafting new types of materials and quantum technology devices. University of Cambridge researchers tracked the atoms' movement at speeds too fast for conventional microscopes to capture.

Optimizing Two-Dimensional Materials for Potential Applications

Two-dimensional materials, such as graphene, could enhance the performance of currently used and newly introduced devices due to their distinct properties, such as exceptional conductivity and strength. These materials have an extensive range of potential applications, from drug delivery and bio-sensing to quantum computing and quantum information. To reach their full potential, however, the two-dimensional materials need to be fine-tuned using a controlled growth process.

These materials are created as atoms "jump" onto a supporting substrate before they ending up in a growing cluster. Tracking this process would allow scientists to more effectively manage the completed materials.

However, for most of the materials, the process happens so fast and at extreme temperatures that it can only be tracked through snapshots of a frozen surface, taking a single moment instead of the whole process.

Helium Spin-Echo Technique

Researchers from the University of Cambridge monitored the full process in real-time at comparable industry-standard temperatures. They used the "helium spin-echo" technique that is akin to magnetic resonance imaging (MRI) but utilizes helium atom beams to illuminate a target surface, just like the light sources in conventional microscopes.

With this technique, scientists can do real-time MRI-like experiments as atoms scatter. "If you think of a light source that shines photons on a sample, as those photons come back to your eye, you can see what happens in the sample," the study quoted senior author Dr. Nadav Avidor of the University of Cambridge Cavendish Laboratory as saying.

Using Helium Atoms Instead of Photons

In lieu of photons, the researchers utilized helium atoms to see what happens on the sample's surface. The helium's interaction with the atoms at the surface infers the motion of the surface species.

Utilizing a sample of oxygen atoms traversing on the surface of ruthenium metal, the scientists took note of the spontaneous breaking and creation of oxygen clusters, with a few atoms in size, and the atoms that swiftly diffuse between the clusters.

While the technique is not new, Avidor said, this is the first time it is utilized to gauge the two-dimensional material's growth.

"If you look back on the history of spectroscopy, light-based probes revolutionized how we see the world, and the next step-electron-based probes-allowed us to see even more," Avidor stressed.

"We're now going another step beyond that, to atom-based probes, allowing us to observe more atomic scale phenomena. Besides its usefulness in the design and manufacture of future materials and devices, I'm excited to find out what else we'll be able to see," he further said.