Experimenting in the lab does not always result in a fundamental breakthrough; however, 2021 has been a good year for matter physics. Recently, a research team have built a Wigner crystal comprised solely of electrons, which was initially proposed 90 years ago. The only-electron made crystal is also shown in the images.
According to research published in the journal Nature, scientists wedged the electrons in an electric field between two atom-thin layers of tungsten disulfide and tungsten diselenide. The atoms in those compounds are few distances apart, so the overlapping layers created a honeycomb-shaped pattern of lower-energy regions, which also helped the electrons to settle down. The handling of the electrons is a spectacular experimental feat that has previously defied the most advanced physics laboratories.
Various other scientists also claimed to have made Wigner crystals, with some compelling findings. However, no one has ever shown photographic evidence of their crystal before, said study co-author and the University of California, Berkeley physicist Feng Wang.
“If you say you have an electron crystal, show me the crystal,” he said.
Since catching the crystal’s image through a camera would have been impossible, the scientists had to take a smart approach. The image was captured with a scanning tunnelling microscope (STM), which uses a probe to pinpoint the precise location of gridlocked electrons by analysing how they react to a little burst of energy.