Artificial materials created atom-by-atom

Working at a temperature of four degrees Kelvin, the researchers used a scanning tunnelling microscope (STM) to arrange vacancies in a single layer of chlorine atoms supported on a copper crystal.

"The correspondence between atomic structure and electronic properties is of course what happens in real materials as well, but here we have complete control over the structure. In principle, we could target any electronic property and implement it experimentally," says Dr. Robert Drost who carried out the experiments at Aalto University.

Using their atomic assembly method, the research team demonstrated complete control by creating two real-life structures inspired by fundamental model systems with exotic electronic properties.

The approach is not limited to the chlorine system chosen by the research team either. The same method can be applied in many well-understood systems in surface and nanoscience and could even be adapted to mesoscopic systems, such as quantum dots, which are controlled through lithographic processes.

"There are many fascinating theoretical proposals that don't exist in real materials. This is our chance to test these ideas experimentally," explains Academy Research Fellow Teemu Ojanen at Aalto University.