Australian scientists claim technological breakthrough in quantum computing

Australian scientists have claimed a technological breakthrough after building the first quantum logic gate out of silicon and thereby clearing the final hurdle to making silicon-based quantum computer processors a reality.

"What we have is a game changer," team leader and University of New South Wales (UNSW) Professor of Electrical Engineering, Andrew Dzurak, told reporters in Sydney on Tuesday.

Quantum computers are used to solve computing challenges beyond the reach of today's fastest "supercomputers".

"A quantum computer uses the most fundamental processes of quantum mechanics...superposition and entanglement," the study's lead author, published in the scientific journal Nature on Tuesday, Dr Menno Veldhorst, said.

In normal silicon computer chips, data is rendered in either one of two states: a 0 or 1, alternating on neighbouring bits.

However in quantum computers, data can exist in both states simultaneously, storing itself in the "spin", which is associated with the electron's tiny magnetic field, holding exponentially more information.

Dzurak and Veldhorst's team reconfigured the transistors that are used to define the bits found in normal silicone computer chips - or classical computers - and turned them into their own quantum-bit (qubit).

The team then created a logic gate whereby the two bits 'talked to each other', a first for quantum computing.

"If quantum computers are to become a reality, the ability to conduct one-and two-qubit calculations are essential," Dzurak said.

The team's research means all of the physical building blocks for a silicon-based quantum computer have been successfully constructed, allowing the engineers to now focus on actually building a quantum computer.

However, they now must seek the 50 to 100 million Australian dollar (35.4 -70.8 million U.S. dollar) investment to build a prototype full-scale silicon quantum processor - in collaboration with industry.

"That's the sort of level that requires commercial ventures, either [venture capital] or industry to invest, and we're keen to talk to potential partners," Durak said, noting talks have already begun.

"It could be that this technology requires a consortium rather than just one company."

Provided they have investment, Dzurak said they will have a working quantum computing processor in five years.

"Because of the reliability you get from industrial manufacture and the simplicity of our design, we're very well placed to achieve that goal," Dzurak said.

The researchers focused on existing silicon technology for better commercialization despite initial investments in the physical systems for quantum computing technology, which would require new technologies and manufacturing processes.

"An existing chip manufacturing plant currently costs around one billion dollars to build and invest in," Dzurak said.

"If we can leverage off that, then we've got a great head start for commercialization."

Silicon is also a great host for the fragile quantum bits which and be easily scrambled and data lost, Dzurak said.

Quantum computers have the potential so solve the many important problems faced by the society.

"It has been suggested (quantum computers) can help solve world energy and pollution problems," though more research is needed, Veldhorst said.

On the consumer level however, we won't be seeing a quantum- computing phone anytime soon.

"We're much further off in application of consumer electronics than for the big data companies like Google and Facebook," Dzurak said, noting the low temperatures needed for quantum computing.

"We envisage - to quantum computers at least - for the foreseeable future, the next two decades, to be via the cloud, via remote data centers that you access over the internet.

"It's really largely the financial sector, the research sector, the medical sector that are probably going to have the first applications for these types of chips." Endi