A collaborative project involving scientists from TU Wien (Vienna, Austria), RWTH Aachen (Germany) and the University of Manchester (UK) has created an artificial atom in graphene that opens up possibilities for quantum computing, as their properties can be directly tuned.
Artificial atoms can be viewed as prisons for electrons; Under such confining conditions, electrons often exhibit properties different from their usual characteristics. But like their counterparts in regular atoms, electrons in these structures (also called quantum dots) can also be made to occupy discrete quantum states. "In most materials, electrons may occupy two different quantum states at a given energy. The high symmetry of the graphene lattice allows for four different quantum states. This opens up new pathways for quantum information processing and storage" explains a researchers from TU Wien. However, creating well-controlled artificial atoms in graphene turned out to be extremely challenging.
The method employed by the team uses an electric field to trap electrons and a magnetic field to force them into tiny circular orbits. This method overcomes the problem created by the lack of smooth edges on any piece of graphene. In addition, the new method has the advantage of scalability, since it should be possible to fit many artificial atoms on a small chip in order to use them for quantum information applications.