New 'flip-flop' qubits may make large-scale quantum computer production a reality soon

Researchers from Australia have designed a whole new type of qubit which they believe will make it easier to build ultra-powerful quantum computers at a large scale.

A team from the University of New South Wales, Australia claim to have devised a new qubit - the smallest unit of quantum information - called "flip-flop qubits", based on silicon that can be scaled up without losing communication between them, reports New Scientist.

For silicon-based quantum systems to function, the distance between qubits has to around 10 and 20 nano metres which leaves little room to place any electronics between them and build a working computer.

Guilherme Tosi, from the University of New South Wales, part of this research said that, "If they're too close, or too far apart, the 'entanglement' between quantum bits – which is what makes quantum computers so special – doesn't occur."

However, with the new finding qubits can now communicate over distances of up to 500 nanometres and this might provide enough space to actually "cram other things between qubits," says Andrea Morello who leads the research.

Instead of making silicon-based qubits from the electron, or the nucleus of a single phosphorous atom, Morello's team makes use of both the nucleus as well as the electron of a phosphorous atom to create one qubit inside a layer of silicon, reports New Scientist.

Qubits that operate within silicon systems, interact through electric fields and researchers have shown that it is possible to extend the reach of those fields by "pulling" the electron away from the nucleus of the said atom, according to the report.

The proposed system will involve a silicon chip within which the flip-flop qubits will be placed and connected with a pattern of electrodes and will be then cooled down to near absolute zero and immersed in a magnetic field.

The binary value of the qubit is determined by its "spin", meaning if the spin is up for the electron and down for the nucleus it is a 1, the other way around will be a 0.

"This makes the building of a quantum computer much more feasible since it is based on the same manufacturing technology as today's computer industry," Morello said.

According to a Reuters report, the new technology would allow chips for quantum computers to be mass-manufactured, a goal that has so far eluded other researchers.

Simon Devitt at Macquarie University in Sydney said that this method would overcome a few of the hurdles that are holding back silicon-based systems and that it could lead to developing a system where a computer with millions of qubits. He also added that quantum computers using silicon were less prone to errors than other types.

However, Morello has made it clear that the new method is still under development.

"This is a theory, a proposal - the qubit has yet to be built," she said. "We have some preliminary experimental data that suggests it's entirely feasible, so we're working to fully demonstrate this."