Antennae signal new qubit architecture

Quantum computing may be only just out of the realms of science fiction, but already there is an issue for a standards body to address. Researchers in Austria have come up with a totally new architecture for the exchange of quantum information: quantum antennae.

The proposal comes from the same University of Innsbruck research group, led by Prof Rainer Blatt, responsible for the building an entire entangled byte of quantum computer. Back then, Blatt used an electromagnetic ion trap to assemble the entangled particles. But he says this approach won’t scale to the large numbers of particles needed for a practical quantum computer. Instead, research has focused on building a computer from a series of small registers which have to be linked.

In this scenario: "the particles oscillate like electrons in the poles of a TV antenna and thereby generate an electromagnetic field," Blatt says in the university announcement. "If one antenna is tuned to the other one, the receiving end picks up the signal of the sender, which results in coupling."

The researchers built a miniaturised ion trap with a double-well potential. They used this to trap calcium ions. The wells were separated by 54 micrometers, and by applying a voltage to the electrodes of the ion trap, the oscillations frequencies of the ions were matched.

"This resulted in a coupling process and an energy exchange, which can be used to transmit quantum information," he concludes. "The new technology offers the possibility to distribute entanglement. At the same time, we are able to target each memory cell individually."

These microtraps could then form the basis of a new quantum chip where ions communicate with each other through electromagnetic coupling.

More details in the University announcement here.