Trapped ions that form a crystal are one of the technologies that can be used to make a quantum computer. But when the system is scaled up to large ion crystals this method gets very slow. Complex arithmetic operations cannot be performed fast enough before the stored quantum information decays.
A Stockholm University research group may have solved this problem by using giant Rydberg ions, 100 million times larger than normal atoms or ions. These huge ions are highly interactive and, therefore, can exchange quantum information in less than a microsecond.
Rydberg ions form small antennas for exchanging quantum information and thus make it possible to realize particularly fast quantum gates. The interaction between Rydberg ions is not based on crystal vibrations, as with ions trapped in crystal form, but on the exchange of photons. The fast interaction between the Rydberg ions can be used to create quantum entanglement. (SciTechDaily)
The paper has been published in Nature.