RU scientists expect atomic information storage at room temperature
Researchers at Radboud University have successfully used a new method to store information on an atom. The scientists demonstrated the technique at low temperatures, but expect it to work at room temperature as well.
It involves magnetic storage on a single atom. The Nijmegen team is not the first to do this; an IBM research team already succeeded in this in March last year. A problem in the attempts at atomic information storage is stability. Magnetic atoms are extremely sensitive to their environment for this application.
Previous experiments made use of the rotational momentum, or angular momentum of electrons. The electrons in an atom rotate in orbit around the nucleus, but they also rotate themselves. The amount of spin creates magnetism. To be able to use this for information storage, it is necessary that the rotation of the atom is stopped. The IBM researchers succeeded, but the experiments only succeeded at -233 degrees Celsius.
For their demonstration, the researchers at Radboud University used a cobalt atom on a surface of semiconducting black phosphorus. For the storage of information, the team created a difference in energy between the electron orbits of the cobalt atom. The state of the orbits can be read and written electrically without the spin sensitivity of other methods.
The Nijmegen invention also produces four separate states, which opens the way to multibit registers. The reading was done with a scanning tunneling microscope in a vacuum at a temperature of -268.75 degrees Celsius. However, the researchers expect that a greater difference in energy between the electron orbits can be created. In combination with the stability, this puts operation at room temperature within reach.
The researchers warn that a practical application is still a long way off. The research was published in Nature Communications under the title An orbitally derived single-atom magnetic memory. Nature Communications.
Observed ground states of the cobalt atoms