Much of Australia’s international reputation in quantum technologies research can be attributed to the Australian Research Council (ARC) Centre of Excellence in Quantum Computation and Communication Technology (CQC2T). In February, the centre officially launched the next seven years of its operations.
The CQC2T evolved from a Special Research Initiative, which was established at the University of New South Wales (UNSW) in 2000 and then tranformed into an ARC centre of Excellence in 2003. Led by Professor Michelle Simmons it is now an international collaboration involving seven Australian universities and more than 25 partners.
The ARC's total investment in the project amounts to around $80 million to date, including a Centres of Excellence grant of $33.7 million awarded in 2018.
The CQC2T has also been supported with $10 million each from Telstra and the Commonwealth Bank, as well as $26 million from the federal government through its National Innovation and Science Agenda (NISA).
The investments are a testament to the success the centre had with developing quantum processes in silicon and optical platforms, and secure communication tools these eventually are to be linked to.
For example, the centre most recently announced the development of photonic microchips that will be key to a large-scale photonic quantum computer.
Researchers at the centre have also advanced the development of quantum processors that are able to run error corrected algorithms and can transfer information across networks with absolute security.
But it is the centre’s unique research of quantum computing in silicon that has become one of the great hopes for Australian research and innovation. The promise is that by utilising silicon, which is already at the base of current computer technology, it will become easier to scale research outcomes upwards into large circuits.
The centre is indeed renowned world-wide for being able to create atomically precise devices in silicon.
Other major technology breakthroughs include the use of the spin, or magnetic orientation, of an electron bound to a single phosphorus atom embedded in a silicon chip to read and write information. The research was published in a landmark paper in the journal Nature in 2012.
Three years later, the team led by Professors Andrew Dzurak and Andrea Morello from the UNSW reported, again in Nature, a silicon-based quantum logic gate that allows calculations to be performed between two quantum bits, or ‘qubits’ - the quantum equivalent of conventional computer bits. Getting qubits to 'talk' with each other had been a major hurdle in the development of a quantum computer in silicon.
Also in 2015, a team led CQC2T deputy director Professor Lloyd Hollenberg from the University of Melbourne used atomic-scale qubits aligned to control lines (essentially very narrow wires) to establish a silicon-based 3D chip architecture.
Most recently, in 2019, a team led by Professor Michelle Simmons then demonstrated that layers of atomic-scale qubits could be aligned in a 3D-device with nanometer precision. Reported in Nature Communications, the device delivered qubit states with very high fidelity within one single measurement.
“We are working systematically towards a large-scale architecture that will lead us to the eventual commercialisation of the technology," Professor Simmons commented.
Simmons is also the founder and director of UNSW spin-off Silicon Quantum Computing, which aims to develop a 10-qubit silicon quantum computer by 2022.
However, 10-qubits won't make a quantum computer that is able to perform practical applications, or even reach quantum supremacy, the holy grail of achieving performances with a universal quantum computer that are beyond the capability of any classical computer.
However, there is more than one way to skin a cat, or to build a quantum computer for that matter, and silicon-based super computing has been only one of several approaches looked at. In fact, alternative ways to generate qubits, such as using superconducting materials cooled to extreme temperatures, have been more popular.
And there is now increasing investment around the world.
Late last year, the US passed a National Quantum Initiative Act into law that aims for a US$ 1.25 billion government investment in quantum technology research over an initial 5-year period.
The European Union has a €1 billion over 10-years Quantum Flagship in place to invest in quantum related research, including the development of a workable quantum computer.
The German goverment separately provides €650 million in funding for research into quantum technologies.
China has also embarked on an ambitious research effort, with investments estimated at several billions of dollars. And then there is Canada, which has been a leading driver of quantum technologies for more than a decade, including through the Institute for Quantum Computing at the University of Waterloo established in 2002.
In the race are also private firms, notably IBM, Google and Microsoft.
The first commercially available quantum computer, however, has been developed by Canadian firm D-Wave, and organisations such as NASA are now paying millions of dollars for it, despite its approach, a process called quantum annealing, being considered to largely limit its functionality to optimisation problems.
IBM is offering access to a cloud based quantum computer system that uses superconducting materials, and recently it announced the IBM Q System One, a 20-qubits computer touted to be “the world’s first fully integrated universal quantum computing system designed for scientific and commercial use.”
It is still far off from being ready for practical uses, but it does provide a glimpse into the future.
What drives this interest is the expectation that large-scale quantum computers will be exponentially faster in solving certain complex problems than today's computers, and thus facilitate transformational applications across many levels of society.
This is based on the peculiar characteristics of quantum mechanics.
Processes in classical computing are calculated through a linear sequence of bits which can have the value of either 0 or 1. But in quantum computing the analogues processing unit, the quantum bit, can at any single point in time represent both 0 and 1, or a combination of both. This phenomenon, known as 'superposition', means that a quantum computer can potentially perform multiple computations simultaneously, and this could be particularly useful for problems that have lots of variables.
However, a recent major review of the technology by the US National Academy of Science, Engineering, Medicine has pointed out that despite recent progress developing a large-scale, and also error-corrected universal quantum computer (errors are a major problem with the technology) will be extremely challenging, if not impossible. According to the Academy, quantum computers are also unlikely to ever replace classical computers (which are even needed to correct quantum errors).
"...recent advances have led to an explosion of interest in quantum computing worldwide; however, with this interest also comes hype and confusion about both the potential of quantum computing and its current status. It is not uncommon to read articles about how quantum computing will enable continued computer performance scaling (it will not) or change the computer industry (its short-term effects will be small, and its long-term effects are unknown)," the report finds.
This does not mean, though, that investing into quantum technologies will be all in vain.
On the contrary, the Academy's report finds that while the feasibility of a large-scale quantum computer is not yet certain, the benefits from the research are likely to be large, with potential spill-overs to other near-term applications.
An example for that was provided in Australia a few years ago with research from the University of Melbourne in collaboration with CQC2T resulting in a quantum molecular microscope capable of imaging the structure of a single bio-molecule, providing a new tool for biotechnology and drug discovery.
A recent report by Deloitte Global predicts that quantum computers could become new extremely powerful supercomputers, but that there use will be less important for everyday users and enterprises.
According to the report, the quantum supercomputer market of the future will therefore be more of the size of today's supercomputer market, around US$50 billion, than anywhere near that of the US$1 trillion market of classical computing devices.
"Even in 2030, none of the billions of smartphones, computers, tablets, and lower-level enterprise computing devices in use will be quantum-powered, although they may sometimes or even often use quantum computing via the cloud.
In the period leading up to fully functional quantum computers entering the market, early-stage products, so called Noisy Intermediate Scale Quantum computers, will be useful for some applications, and potentially be worth hundreds of millions of dollars per year in the 2020s.
Deloitte's report also notes another emerging commercially important area of quantum computing: a quantum-safe cyber security industry. As quantum computing potentially will be a threat to current cryptosystems, through a so called Shor's algorithm, enterprises and governments should start preparing for it, "not when it happens, since by then it will be too late".
