Quantum technologies find a way

The establishment of the Australian Research Council Special Research Centre for Quantum Computer Technology in 2000 marked the beginning of a serious Australian commitment to the development of quantum science.

This was followed by the establishment of the Centre for Quantum Computer Technology in 2003 and the Centres for Quantum Computation and Communication Technology and for Engineered Quantum Systems in 2011.

This long-term project began with solid support for basic research and now, more than 15 years later, Australia is beginning to reap the rewards of our vision and investment. Our researchers have become leaders in their fields, spearheading advancements in quantum sensors, quantum computing and other quantum engineered systems.

Quantum sensing

A new generation of quantum sensors has the potential to transform the way we see the world – with applications from medical diagnostics and the manipulation of viruses and proteins to navigation and environmental monitoring. Researchers at the University of Queensland’s Precision Sensing Initiative and the Australian Centre for Engineered Quantum Systems have led one such development in single-molecule biosensing.

 Their new approach harnesses light to track and analyse biomolecules and is significant because where previous technologies used light to examine individual biomolecules and risked damaging specimens, theirs does not. In fact this new technique not only achieves state-of-the-art sensitivity, but also does this with a light intensity lower than has been previously possible by a factor of 10,000. 

This sensing technique enables tracking of biomolecules around 3.5 nanometres in size, and the monitoring of surface–molecule interactions over extended periods of time. It is the first technique of its kind that uses sufficiently low intensities to detect single unlabelled biomolecules without modifying their behaviour, growth or viability. 

This enables the study of the nanoscale machinery of life in its native state, like the motor molecules that unravel DNA and produce energy within cells. This work compliments the 2017 Nobel Prize in Chemistry, awarded for cryogenic electron microscopy of the structure of single molecules, but offers the prospect of extending those advances into living biological systems.

Quantum computing

Quantum computing is another area where Australia is forging ahead. It’s a field not many Australians are familiar with, and differs from traditional computing in a few ways.

When you look at the processing power of a traditional computer, you are working with bits – representing a 0 or a 1. If you have 4 bits, they can be arranged in 16 different ways (0001, 0010, 0100 etc.), but a classical computer can perform only one operation at a time, using only one configuration of these 4 bits.

In a quantum computer, the same number of quantum bits (4 qubits) can be arranged in the same 16 ways, but they can be in all of these arrangements at once, and the quantum computer can perform operations on all of these configurations. This means much faster processing for many applications.

The main challenge with a quantum computer is scaling the system. In Australia, we have been working hard to develop quantum computers that are made of phosphorus and silicon, but have encountered roadblocks preventing us from progressing beyond the two-qubit stage. 

Researchers at the ARC Centre of Excellence for Quantum Computation and Communication Technology have proposed a way this might be solved, using ‘flip-flop’ qubits.

These qubits can be set much further away from each other, and may achieve increased stability to allow silicon quantum computers with more than two qubits to be produced. 

Quantum business

Multinationals are now coming to Australia to pursue research and development in quantum science in partnership with Australian universities.

The University of Sydney has established the Sydney Microsoft Quantum Laboratory, which represents the largest investment in quantum technology in Australian history. Additional to their work with qubits, this laboratory is also working to develop better classical technology so that it can keep up with the developments in quantum computing.

Similarly, the launch of UNSW’s quantum computing company – Silicon Quantum Computing Pty Ltd – following work with a variety of Australian businesses, signals another step towards leading the world in this field.

With continued and steady support for this significant field of research, Australia will reap the benefits from these initiatives for years to come.

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This article has been written as part of a two-part series for Science meets Parliament. The event brings researchers to Canberra to meet with Parliamentarians, and this year will highlight the value of investing in basic research. To take part or learn more, visit the Science & Technology Australia website.