Swastik Kar, an associate professor of physics at Northeastern University, said: “When such phenomena are discovered, imagination is the limit. “It could change the way we can detect and communicate signals.
“It could change the way we can sense things and the storage of information, and possibilities that we may not have even thought of yet.”
The ability to move, manipulate and store electrons is key to the overwhelming majority of modern technology.
In a new paper published in Nanoscale, the researchers have described a way to make electrons do something entirely new – distribute themselves evenly into a stationary, crystalline pattern.
Professor Kar added: “I’m tempted to say it’s almost like a new phase of matter. “Because it’s just purely electronic.”
The phenomenon appeared while the researchers were running experiments with crystalline materials are only a few atoms thick, known as two dimensional materials.
Such materials are constructed in a repeating pattern of atoms so thin their electrons can only move in two dimensions.
Stacking these ultra-thin materials can create odd effects because the layers interact at the quantum level.
Professor Kar’s team were examining two such 2-D materials, bismuth selenide and a transition metal dichalcogenide, layered on top of each other like sheets of paper.
The team at first assumed the result was a mistake.
The crystalline structures of 2-D materials are too small to observe directly, so physicists use special microscopes that fire beams of electrons instead of light.
As the electrons pass through the material, they interfere with each other and create a pattern.
Using complex maths, the specific pattern was used to recreate the shape of the 2-D material.
When the resulting pattern revealed a third layer that couldn’t be coming from either of the other two, the researcher presumed something had gone wrong in the creation of the material or in the measurement process.
Although similar phenomena have been observed before, this was only at extremely low temperatures, while the researchers’ observations were at room temperature.
But after repeated testing and experiments led by doctoral student Zachariah Hennighausen, their results remained the same.
There was a new lattice-style pattern of charged spots appearing between the 2-D materials.
And that pattern changed with the orientation of the two sandwiching layers.
Arun Bansil, a university distinguished professor of physics at Northeastern, believes the phenomenon is caused because electrons in a material are always bouncing around.
This is because they are pulled on by the positively charged nuclei of atoms and repelled by other negatively charged electrons.
But in this case, something about the way these charges are laid out is pooling electrons in a specific pattern.
“They produce these regions where there are, if you like, ditches of some kind in the potential landscape, which are enough to force these electrons to create these puddles of charge.
“The only reason electrons will form into puddles is because there’s a potential hole there.”
These ditches, so to speak, are created by a combination of quantum mechanical and physical factors.