Key points
- Quantum theory has already helped created many of the technologies we use every day such as computers, mobile phones, lasers, medical imaging and more.
- The world is in a second quantum revolution where we are creating new devices that will solve some of society's greatest challenges.
- Australia punches above its weight in driving basic research in quantum science. We now need to translate this homegrown expertise into a thriving national industry.
Year of Quantum
The United Nations has officially declared 2025 as the International Year of Quantum Science and Technology. This acknowledges both the contribution and opportunities for quantum science to make the world a better place for everyone.Around 100 years ago, the key elements of quantum mechanics were formulated. Since then, they have proven highly successful in describing the behaviour and properties of matter at a microscopic scale. Despite some of its counterintuitive predictions, quantum theory has stood up to every test or measurement we’ve devised, and each time has passed with astonishing accuracy. The knowledge we’ve gained has been crucial to creating many of the technologies that are central to our modern way of life. This includes semiconductors that power computers and mobile phones, lasers, medical imaging and many others.
Currently, the world is going through a second quantum revolution where we are creating new devices, that exploit uniquely quantum behaviours at the heart of their operation (behaviours such as superposition, tunnelling or entanglement). These “Quantum 2.0” technologies are now opening new possibilities for capturing, processing and sharing information.
Powerful computing
The area that’s attracted the most attention is quantum computing, because of its potential for transformative change. A large quantum computer could be transformational to society, as it can solve a selection of problems that we can’t easily do now. Some of the possibilities are in optimising traffic flow, designing molecules that can collect even more energy from the sun than today’s rooftop solar panels and increasing the efficiency of fertiliser production to improve global food security. But, quantum computing also requires significant further development, making it a high-risk, high-reward endeavour.We’re currently in the era of Noisy Intermediate Scale Quantum computers (NISQ) where hardware noise and errors in the fragile quantum systems limit the size and complexity of applications. Reaching a level of ubiquity and performance where quantum computers are capable of outperforming computers based on classical physics is still some decades off, and it is worth remembering that the real advantages of quantum computing have only been proven theoretically for a handful of select (but nonetheless significant) computational problems. Scientists and engineers are working hard to identify the best way to make a quantum computer, and it’s an open bet as to which technology, or selection of technologies, will be successful.
Looking around the globe at quantum computing hardware, several vastly different approaches are being pursued. Australia has invested nearly $1B into a company, PsiQuantum, which is using particles of light (photons) as the ‘quantum bits of information’ (called qubits) to build a useful quantum computer. Other companies, including IBM and Google, use superconducting circuits to store and manipulate information. Then there are others who trap arrays of individual atoms and address these with lasers. Further platforms include trapped arrays of ions, doped silicon, semiconductors and diamonds. Several of these are being developed in Australia. With each of these approaches, comes different challenges and bottlenecks that need to be overcome before we’ll have a quantum computer that would generally be classified as “useful”. Nonetheless the progress in the last decade has been staggering.
It’s also critical that we have the software and algorithms that will actually run on a quantum computer, and make it do something useful despite the inevitable noise and errors that can build up in quantum devices. Without this, a computer would be little more than a collection of (expensive) high-tech toys.
While we are not developing quantum computers at CSIRO, we are very interested in working out how they can be made useful. For example, we have teams answering key questions like, “When we have a quantum computer, what should we get it to do?”. Some of the most promising early applications appear to be in materials design and chemistry, which are inherently quantum systems that are difficult to model on classical devices. Other promising avenues are artificial intelligence and machine learning where quantum approaches can make machine learning algorithms more robust and less easily tricked by noise or deliberate hacks.
Information security
One of the problems that a quantum computer could solve quickly is factorising large numbers. This classically difficult task is the basis of standard encryption schemes. It could also mean that quantum computers pose a threat to the security of digital information and communications. However, quantum technologies may in fact come to the rescue and provide the next generation of secure communications technologies. One way this could happen is through a highly non-intuitive property of quantum physics known as entanglement, where the laws of physics can guarantee the safety of shared data. Quantum communications based on entangled states can ensure that attempts to intercept or eavesdrop on a signal will destroy the information. So, any attempt to hack a quantum communication channel will be pointless and immediately detected.We have teams at CSIRO working to develop secure applications – including post-quantum cryptography and quantum key distribution – and secure communication devices. In one example, we are developing free-space optical quantum communication channels to transmit information stored in quantum states of light from a base station to a receiver some distance away. While our experiments so far traverse several kilometres across the Adelaide Hills, this work might lead to quantum-secured Earth-to-satellite communications.
Quantum communications may also provide solutions for geo-location, as back-up or supplement to the GPS we’ve all come to rely on. Classical GPS signals can be easily disrupted or mimicked, which can impact military and commercial operations like airplanes and delivery services. Or consider that GPS doesn’t work underground at all. Quantum secured time transfer may provide a means to overcome this vulnerability. This can be complemented by a new generation of quantum inertial that can track exactly where you move from a known starting location, independent of a GPS signal from a satellite (see below).
Sensing
Quantum sensing is one of the most promising near-term technologies. Indeed, sensing is already used in several industries today, including mining, but there are some exciting new developments just around the corner.Quantum systems are by their nature very fragile, such that even very weak signals like changes in temperature or magnetic field will ‘upset’ or perturb the quantum state in a way that we can measure. This means we can detect and quantify signals in a more sensitive way than previously possible. In some cases, quantum technologies can offer significant practical advantages, like enabling smaller and more portable devices for medical diagnostics, or measuring tiny changes in the earth’s magnetic field that can be used for geolocation or detection of certain materials.
At CSIRO we have a range of active projects, from sensing magnetic fields in deposits of minerals underground to pinpoint what’s there and then minimise the environmental impact of locating and extracting the precious minerals, to bio-compatible quantum sensors that can provide an accurate measure of iron levels in blood.
What’s next for Australia’s quantum industry?
For decades, Australia has, per capita, punched above its weight in driving basic research in quantum science. There is now a clear opportunity to translate this homegrown expertise into a thriving national industry. Australia could be an internationally significant player in the quantum sector. This opportunity is captured in CSIRO’s 2020 quantum roadmap, “Growing Australia’s Quantum Technology Industry” and the 2023 National Quantum Strategy.
Making this a reality will require commitment, coordination and innovation across government, the research sector and industry. It's impressive to see the progress that’s been made over the past two decades and much of this is now ripe for translating to commercial applications. The scene is set but will require a strong workforce (of both quantum and non-quantum people), infrastructure, investment and —real-world applications as the foundation of a strong national quantum industry.
Chris Vale is a professor of physics and Director of CSIRO’s Quantum Technologies Future Science Platform.
This article was republished with permission from Manufacturer's Monthly.