Telecoms.com periodically invites expert third parties to share their views on the industry’s most pressing issues. In this piece Dr Andrew Shields, Head of the Quantum Technology Division at Toshiba Europe, makes the case for quantum computing.

We are witnessing an innovation arms race in quantum computing. Last year, $1.7 billion was announced in start-up funding alone, more than double the amount raised just one year before in 2020. This is largely due to a huge acceleration in private investment from organisations across the globe, who are competing to realise the computational benefits of quantum.

While quantum computers have been discussed in academic circles since the early 1980s, research remained modest and essentially theoretical until scientific bodies began to hit more significant milestones in the last decade. In the wake of these advances, private tech companies have begun their own major research and development programs.

IBM released the first integrated quantum computing system in 2019 – IBM Quantum System One. Shortly after, Google’s 54-qubit Sycamore processor completed a computation in 200 seconds that would have taken the most powerful classical supercomputer in the world 10,000 years. Quantum computers not only exist, but Fujitsu predicts that it will make its quantum computing technology commercially available next year.

There is understandably huge excitement about what this influx of innovation could mean. Quantum makes possible applications that simply aren’t practical with traditional technology, and dramatically accelerates many that are.

But as we reach the brink of the commercialisation of quantum computing, there has also been increasing alarm from academics and industry bodies about its impact on our data security infrastructure. These anxieties have been an ongoing counterweight to the benefits of the technology.

However, thanks to exciting new breakthroughs in quantum-safe security, we are closer to being able to enjoy these benefits without paying a cost in the integrity of our data security.

One of the most exciting applications of quantum computers is to medical research and development. Drug research typically requires the evaluation of the interaction of huge numbers of variables within our body chemistry with the components of the drug, observing their impact over time on the conditions they are targeting, along with side effects.

Accurately modelling all these interactions is time- and investment-intensive, particularly as traditional computers have to use sequential methods to model each possibility in turn. New drugs currently take an average of $2 billion and more than ten years to reach the market after discovery.

Quantum computers, which use simultaneous rather than sequential calculation, would dramatically speed up this process. Indeed, they will be able to model situations thousands of times faster than powerful computers can today. As a result, drug design and discovery will be faster and less expensive.

Another important application is the discovery of sustainable alternatives to currently used materials, energy, feed, and much more besides. As McKinsey states, quantum computing is already being applied to a wide range of research including: “curbing methane produced by agriculture, making the production of cement emissions-free, improving electric batteries for vehicles, developing significantly better renewable solar technology, finding a faster way to bring down the cost of hydrogen to make it a viable alternative to fossil fuels, and using green ammonia as a fuel and a fertiliser.”

Meanwhile, other research is producing indirect benefits. Quantum computers are being used to improve the design of catalysts, for example. The global economy is dependent on the production of vast amounts of chemicals each year, many of which are produced using electrolysis. Making the catalysts for electrolytic processes more efficient could not only significantly reduce their cost, but also the impact they make on the environment.

While there are exciting early areas of application, much of the conversation about quantum’s use for sustainability remains theoretical or nascent. However, there is huge scope for development in coming years as its ability to support innovation and optimisation makes it an exciting tool for our most complex problems.

With every new innovation comes the threat of it being used for malicious intentions. The reality is that quantum computers will be capable of easily performing calculations to crack public key cryptography algorithms. These encryption techniques are used to protect much of our valuable data today – from WhatsApp messages to bank transfers.

Indeed, telecoms networks are a key concern, as they carry so much sensitive data every day – the secure transmission of which is absolutely paramount. As we reach the brink of the commercial availability of quantum computers, what happens when these fortresses come down?

A huge amount of investment and research has already gone into the problem of how to create quantum-safe networks; here, Quantum Key Distribution (QKD) has proven an exciting field.

QKD technology takes advantage of the laws of quantum physics to ensure that bad actors cannot decrypt data in transit, even with the use of powerful new quantum computers, while still maintaining security against other high-performance computers.

For telecoms providers, QKD technology offers a way to protect customers from current and future cyber security threats. However, integrating QKD into existing networks has traditionally presented complications.

There have typically been two options, both with a significant downside. Firstly, providers could overhaul their entire network to install additional dark fibres to carry QKD signals. In heavily built-up metro areas this can be highly impractical.

The second option is to transmit QKD signals on existing fibres using wavelength division multiplexing (WDM) – or simply ‘multiplexing’ – techniques, where many different optical data wavelength channels are launched on the same fibre.

However, this method typically meant making compromises to the distance and performance of existing networks. Such obstacles have prohibited many providers from being able to move ahead on the installation of quantum-safe technologies.

New technologies are giving hope to the cause, just as the threat of quantum draws nearer. Toshiba has been pioneering quantum-safe solutions for decades, and we’ve now discovered a technique that will enable multiplexing on the same fibre, without compromising performance.

By separating the QKD and conventional signals onto different wavelengths within the optical fibre, the QKD signal and the secret key can be successfully carried, without impacting performance or requiring a restart of the network, avoiding downtime in critical systems.

While QKD over dedicated fibres has been available for some time, this innovation makes QKD economically viable for the first time, even for complex built-up environments close to the customer. Using this system, it’s possible to easily implement QKD to an existing network infrastructure, without the need to introduce new fibres for the quantum signals – radically reducing the cost of making a current infrastructure quantum-safe. Meanwhile, using this brand-new multiplexing technique, providers can maintain existing performance standards too.

Thanks to these advancements, it’s now possible to be excited about the power of quantum computing and the benefits to society’s most complex issues, without paying the price of our data security.

Andrew Shields leads R&D and business development in Toshiba Europe on quantum technologies.  According to Google Scholar, he has published over 500 research papers and patents in the field of quantum devices and systems, which have been cited over 23,000 times and has a Hirsch-index of >70. He was a co-founder of the Industry Specification Group for QKD of ETSI, and served as Chair for several years.  He serves on the management team of the EU OpenQKD project and leads the AQuaSeC consortium developing next generation quantum communication technology.