Electron beams can be used to heal nano-fractures in crystals instead of causing further damage to them, as initially expected by researchers who now report their surprise findings. Used to power microscopes that examine the smallest materials in the universe, electron beams may also be able to be used to create novel microstructures one atom at a time.
A feat once thought impossible, researchers at the University of Minnesota Twin Cities (UMN) behind the discovery said it had been assumed that using electron beams to study nanostructures carried the additional risk of exacerbating microscopic cracks and flaws already in the material.
“For a long time, researchers studying nanostructures were thinking that when we put the crystals under electron beam radiation to study them that they would degrade,” explained Andre Mkhoyan, a UMN chemical engineering and materials science professor and the lead researcher in the study.
Instead, the researchers say that something incredible happened. Their electron beams did have an effect on these nanofractures, but it was the exact opposite of what they had expected.
“I was studying the cracks in the crystals under the electron microscope, and these cracks kept filling in,” said Silu Guo, a UMN chemical engineering and materials science Ph.D. student. “This was unexpected, and our team realized that maybe there was something even bigger that we should be studying.”
A closer study revealed that what they were seeing was not an illusion. On a very tiny, microscopic scale, they found that several atoms from the crystal they were studying actually moved toward each other before meeting in the middle. This process formed “a sort of bridge” that tended to fill in the fracture that had previously existed, essentially healing the fracture instead of making it worse.
Engineering Microscopic Objects Atom-by-Atom Using Electron Beams
The researchers note that they don’t believe there was anything magical about the specific microscope they were using. Instead, they believe that the ability to heal itself using electron beams is simply part of the makeup of these specific materials.
“Whether it’s atomically sharp cracks or other types of defects in a crystal, I believe it’s inherent in the materials we’ve grown,” said UMN Chemical Engineering and Materials Science Professor Bharat Jalan, a collaborator in the research. But, he added, “it’s truly astonishing to see how Professor Mkhoyan’s group can mend these cracks using an electron beam.”
Initially shocked by the results of their analysis, the press release announcing the potential breakthrough process says, “The researchers showed that the electron beams could be used constructively to engineer novel nanostructures atom-by-atom.”
Such an ability is often treated as the Holy Grail of materials science, where objects can be designed, engineered, and ultimately constructed one atom at a time.
Refining and Improving the Process
Next, the UMN team says they want to explore ways to improve the technique they stumbled upon. This includes looking at changing the dynamics of the electron beams themselves or even changing the temperature of the target crystals to potentially “improve or speed up the process.”
“First, we discovered,” said Mkhoyan. “Now we want to find more ways to engineer the process.”
Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him directly at christopher@thedebrief.org.