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An Australian-led team of scientists have developed the key building blocks needed to make a quantum computer using silicon. Their work was published in Nature.

A research team from the University of Melbourne, the University of New South Wales, and Aalto University in Finland have been able to read out the spin orientation of a single electron on a single engineered atom in a nanoscale device they developed called “the single electron reader”.

This is key technology for "spintronics" which paves the way for a revolution in the next generation of computation and communication technology.

The team that made the breakthrough was led by Prof Andrew Dzurak and Dr Andrea Morello of School of Electrical Engineering and Telecommunications at University of NSW and Professor David Jamieson of the School of Physics University of Melbourne.

Professor David Jamieson said this discovery could unlock revolutionary applications in the silicon industry.

“Silicon continues to be of primary importance for information technology. It’s potential has not yet been fully realised, and this discovery shows is versatility.”

By using silicon—the foundation material of conventional computers, the device opens the way to constructing a simpler quantum computer, scalable and amenable to mass-production.

Professor Jamieson’s team has 20 years of experience with implanting atoms into silicon and other materials for projects involving materials modification and analysis.

His team developed a way of getting the essential dopant atoms (phosphorus in this case) into silicon in a way that was compatible with the advanced nanotechnology developed to read the electron spin in orbit around a single phosphorus atom. 

The team at UNSW utilised advanced nanotechnology for making nanoscale devices led by Professor Andrew Dzurak and very sophisticated instruments for controlling and measuring the devices led by Dr Andrea Morello.

Dr Morello, who is the lead author of the paper said the device detects the spin state of a single electron on the specially engineered phosphorus atom. “The spin state of the electron controls the flow of electrons in a nearby circuit,” he said.

 “Until this experiment, no-one had actually measured the spin of a single electron in silicon in a single-shot experiment.”

The overall team has built on a body of research that has put Australia at forefront of the race to construct a working quantum computer. In 1998 Bruce Kane, then at UNSW, outlined in Nature the concept for a silicon-based quantum computer, in which the qubits are defined by single phosphorus atoms in an otherwise ultra-pure silicon chip. The new device brings his vision closer.

“This breakthough is the key to unlocking the world of quantum computing and the quantum internet of the future, which has been a long time in the making,” Professor Jamieson said.

“We expect quantum computers will be able to perform certain tasks much faster than normal computers, such as searching databases, modelling complex molecules or developing new drugs,” said Professor Andrew Dzurak. “They could also crack most modern forms of encryption.”

“After a decade of work trying to build this type of single atom qubit device, this is a very special moment,” Professor Dzurak said.

Now the team has created a single electron reader, they are working to quickly develop a device for programming the electron spin orientation and create a 2-bit logic gate – the basic processing unit of a quantum computer.

The research team is part of the Australian Research Council (ARC) Centre of Excellence for Quantum Computer Technology, based at UNSW. The paper’s co-authors include Professor Robert Clark, who is now Australia’s Chief Defence Scientist and researchers from Finland’s Aalto University.

The research was funded by: The Australian Research Council Centre of Excellence Scheme, The NSW State Government, the Government of the USA, UNSW and the University of Melbourne.

 

An Australian-led team of scientists have developed the key building blocks needed to make a quantum computer using silicon. Their work was published today in Nature.

Patterned feathers, previously thought to be used only for camouflage in birds, can play an important role in attracting a mate and fending off rivals, a University of Melbourne study reveals.

Ms Thanh-Lan Gluckman, co-author of the paper and Masters of Philosophy student from the Department of Zoology at the University of Melbourne, said this finding brought a new perspective to research in animal communication and evolution.

“The implication of this study is that feathers don’t need to be bright and showy to be used in sexual signaling and hence this changes our understanding of animal communication,” she said.

Hundreds of bird species such as Zebra Finches and Cuckoos have “barred” patterns on their feathers, which are made up of horizontal bars alternating dark and light pigmentation side by side.

“Since Darwin wrote of visual communication in birds, we have known that bright coloured feathers play a role in sexual signaling, for example to attract females. But the role of barred patterns as a communication signal has largely been overlooked,” Ms Gluckman said.

The study was a large-scale comparison of plumage of around 8900 bird species worldwide (90% of all bird species), and was conducted with former University of Melbourne lecturer Dr. Gonçalo Cardoso, now at the Research Centre in Biodiversity and Genetic Resources (CIBIO), Portugal.

The researchers compared barred plumage and other patterns on the body of males, females, and juvenile birds, to assess what they might be used for.

While the researchers found evidence that barred plumage is predominantly used as camouflage, they also found that barred plumage was much more likely to appear only in males, or only at sexual maturity, compared to other patterns.

“Furthermore, we found these differences on the front of the birds, which is an important area for communication during face-to-face interactions, not on their back, which is more useful for camouflage when running away or hiding from predators,” she said.

“This is an exciting finding showing an elegant evolutionary solution to the needs of birds to camouflage as well as to signal to a potential mate or rival.”

The study has been published in the prestigious Journal of Evolutionary Biology.

Patterned feathers, previously thought to be used only for camouflage in birds, can play an important role in attracting a mate and fending off rivals, a University of Melbourne study reveals.

A price on carbon is back on the agenda following yesterday's announcement of a minority Gillard Government says Dr Peter Christoff of the Department of Resource Management and Geography at University of Melbourne, but an emissions trading scheme like the one pushed by Labor in its first term is unlikley.

“In securing Greens' support in the lower house, Labor agreed to the formation of a Climate Change Committee of experts and parliamentarians, to consider the issue of a carbon price. Its composition, mandate and timing are yet to be determined, but the three independents and the Green supporting Labor in the lower house will certainly hasten its work,” Dr Christoff says.

“However Rob Oakeshott and Tony Windsor both opposed the CPRS last year. Meanwhile, the Greens proposed an interim levy but rejected an emissions trading scheme - or any other measure - that rewards or exempts big polluters.”

“So an interim carbon levy, or an emissions scheme which excludes major compensation for big polluters, is now likely - especially once the Greens gain the casting vote in the Senate from the middle of next year," he says. 

The following text comes from the 2010 Hamer Oration held at the University of Melbourne on Thursday August 5, 2010.  The speech was given by Professor Ross Garnaut, a Vice Chancellor's Fellow and Professorial Fellow in Economics at the University. 

As the Federal Government formulates its climate policy, a new analysis released today, shows that political and social will, rather than technical feasibility and cost, are the key obstacles standing in the way of a 100 per cent renewable, zero emissions electricity supply system being implemented in Australia.

Australia could soon benefit from highly sensitive coloured x-ray imaging and powerful new tools to reveal the structure of materials in unprecedented detail and provide major advances in medicine and technology.

Researchers at the University of Melbourne have teamed up with the Sustainable Agriculture Fund (SAF) to tackle the challenges the Australian farming industry will face in maintaining productivity under a changing climate.

The evolution of bird bills is related to climate according to latest research by the University of Melbourne, Australia and Brock University, Canada.

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