To that end the researchers utilized a pair of ytterbium ions as quantum bits, or qubits, each confined to a private vacuum chamber about a meter apart in an experimental system at the Joint Quantum Institute of the University of Maryland and the National Institute of Standards and Technology. (scientificamerican.com)
This was achieved by means of ytterbium ions which were trapped in so - called «radio - frequency ion traps» in ultra-high vacuum and were cooled down to a few millikelvin with the aid of laser light. (sciencedaily.com)
The team has created twin ytterbium clocks that are stable to one part in a quintillion (1018). (newscientist.com)