Researchers Create World's Smallest Swiss Cross Using 20 Single Atoms

Researchers at the University of Basel have developed the world's smallest Swiss Cross, which is made of just 20 atoms. The team stated that the tiny structure is the first big step towards atomic-scale devices.

Scientists moved 20 single atoms on a fully insulated surface at room temperature to create the Swiss Cross.

What makes the device important is that it was made at temperature. Other scientists have tried manipulating atoms on conducting and semi-conducting surfaces. This is the first time that researchers have been able to make atomic-size artificial structure at room temperature.

Also, researchers used several theoretical calculations to find the most efficient way of manipulating single atoms. The study shows that in the future, it might be possible to use atomic-scale device for storage as well as logic gates.

To fabricate the device, researchers placed single bromine atoms on a sodium chloride surface using the tip of an atomic force microscope. The tiny Swiss Cross was made by exchanging chlorine with bromine atoms. The entire structure measures just 5.6 nanometers square. For reference, a nanometer is just one-billionth of a meter.

According to the researchers, this is the first time that 20 single atom exchanges have been made at once.

The study, "Atom manipulation on an insulating surface at room temperature," is published in the journal Nature Communications.

Scientists all over the world are trying to manipulate atoms to make small storage devices. Last year, researchers at IBM and colleagues created a Guinness World Record by developing the smallest movie ever made. The team used thousands of atoms to create the 250 frame movie called "A Boy and His Atom." IBM uses scanning tunneling microscope or STM to move and even manipulate atoms. The STM works at negative 268 Celsius.

Small scale memory storage devices could revolutionize the way we compute. Researchers at IBM have also shown that one bit of magnetic information can be stored using just 12 atoms.

Nanoscale memory, at least the theoretical part of it, isn't a new idea. Richard Feynman, in 1959, had said that someday we will have atomic-sized storage devices. He had estimated that all the printed work since the Gutenberg Bible could be stored in a structure that is just 0.1 mm wide (cube of material 1/200"). 

The team in the present study included Shigeki Kawai and Ernst Meyer from Department of Physics at the University of Basel along with other researchers from Finland and Japan.