Since the 1960s, the rate of progress in every field of scientific inquiry – from drug discovery to climate forecasting, renewable energy to artificial intelligence – has depended, at least in part, on the ability of engineers to build smaller transistors.
Transistors are the electrical switches that process binary code. From the mid-1960s to the mid-2010s, the number that engineers had been able to place on to a single integrated circuit doubled approximately every 12 to 24 months, as the Intel founder Gordon Moore had predicted in 1965 in what came to be known as Moore’s Law.
Less than five decades later, transistors had become so small that, in 2013, Apple was able to produce a smartphone featuring a square chip, measuring just over a centimetre wide, that contained more than one billion transistors – tens of thousands of times more than the computers that accompanied Neil Armstrong and Buzz Aldrin to the moon in 1969.
But as transistors continue to shrink, engineers are increasingly pushing up against the boundaries of physics. It is, after all, fiendishly difficult, and immensely expensive, to build a transistor that is smaller than an atom.
Grappling with this challenge, Jensen Huang – the CEO of Nvidia, the US’s most valuable chip-maker – issued a sombre warning about the pace of technological progress in January 2019. After half a century of exponential development in chip-making, Moore’s Law, Huang warned, was over.
Nevertheless, the multibillion-dollar quest to build ever-more powerful chips has continued. The challenge facing the world’s leading physicists and engineers now is not how to build transistors that are smaller than an atom, but how to harness the forces within atoms to develop an entirely different kind of electrical switch – one that is not simply on or off, like a transistor, but that can exist in both states simultaneously.
This new kind of switch is what quantum physicists call a “qubit” – a quantum bit – and linking qubits together could dramatically increase the number of concurrent computations a computer is capable of processing. The promise is that quantum machines will, as such, be able to carry out calculations it would take the world’s fastest super computer an unfeasibly long period of time to finish.
Just as the invention of the transistor in 1947 defined technological advancement over the following 70 years, quantum experts believe their work creating qubits could usher in a new era of computing that will shape the development of key fields of science once again.
But as the quantum race plays out in universities, tech companies and government research labs around the world, EU officials in Brussels are becoming increasingly fearful about how the technology will develop, who will have access to it and what they will use it for. And the UK, a pioneer in quantum research and just three months into its new trading relationship with the EU, is currently the focus of its concerns.
On 31 March a British company called Quantum Motion unveiled a breakthrough that it claimed could accelerate the development of quantum computing by several decades. While IBM and Google are the world-leaders in the field, the two companies depend on rare and expensive metals to build the “superconductors” that they use to isolate and measure electrons, their representation of a qubit.
Quantum Motion, however, has devised a way to isolate electrons using the silicon transistors found in conventional semi-conductor chips. In its latest experiment, led by the Spanish PhD student Virginia Ciriano-Tejel, the team was able to measure the quantum state of an electron on a chip for nine seconds, demonstrating a level of stability that few other companies have been able to match.
John Morton, a nanoelectronics professor at UCL and a co-founder of Quantum Motion, compares the current race to build quantum computers to the mid-20th century’s furtive computing research. “We’re in this early 1950s where everyone’s trying out these new ways to build quantum computers and many of them are trying quite exotic ways using super conducting circuits or ions,” he told the New Statesman. “The challenge is these very new methods may take a long time to scale up to the point where they can really deliver practical solutions.”
Quantum Motion’s researchers are trying to “short cut this process by taking a technology that already makes not millions but billions of transistors and sticks them on a chip that might be in the computer that you’re working on”, says Morton.
While Google has been able to link together 53 qubits, Morton noted that a million will need to be connected if the promise of quantum computing is to be fully realised. He said researchers are only at the start of that journey and it is therefore possible that his company’s avenue of research could surpass those of the much larger players in the sector.
Quantum Motion’s ground-breaking experiment took place in UCL’s quantum research lab in Bloomsbury, but it used a device that had been manufactured at CEA-Leti, a French, government-funded microelectronics facility in Grenoble. The project was part of the latest phase of the European Union’s €1bn flagship quantum research programme, and is one of the most significant breakthroughs to have emerged from the initiative so far.
However, the UK’s future participation in the programme is now at risk. On the instruction of Thierry Breton, the EU’s internal market commissioner, the UK, alongside Switzerland and Israel, now faces being locked out of the Horizon Europe science programme in areas that may jeopardise national security, including quantum computing and space. Quantum researchers in the UK and across Europe fear that such a move would not only harm the British quantum sector, but Europe’s too. Of the 19 projects in the EU’s Quantum Flagship research programme, which is funded by Horizon Europe, British universities and companies participate in 15.
Nineteen of the 27 EU member states have now pushed back against Breton’s proposals, which have also faced criticism from high-profile scientists across Europe. On 23 March Germany stated that it supports the full cooperation of Israel, Switzerland and the UK in the Horizon Europe programme.
Switzerland has already been tentatively re-included in the programme, and one source with knowledge of the negotiations suggested that a day after Germany’s intervention, it appeared Israel would be too. No formal position on any non-EU state has been taken yet and the UK’s fate remains under review.
None of the quantum physicists who spoke to the New Statesman for this article sought to downplay the security risks that the technology could ultimately pose to nation states.
Much of the internet’s data is encrypted using RSA, an algorithm developed in the 1970s that encodes data by multiplying two large prime numbers. Conventional super computers can easily carry out these computations, but it takes much longer for them to reverse the process and unscramble a code by determining all of the prime numbers that the sum of the two primes could be divided by.
By processing calculations simultaneously, however, a quantum computer could crack these codes much faster. Encryption that could take super computers longer than the age of the universe to decrypt could in the coming years be unravelled by quantum computers in just a few hours.
This poses a huge opportunity, and a major threat, to nation states and their intelligence agencies. Although it is expected that encryption software will have significantly advanced by the time high-functioning quantum computers have been developed, there are fears that agencies may be accumulating encrypted data now that could be decoded in the future.
Graeme Malcolm, the founder of M Squared, one of the UK’s leading quantum computing companies, acknowledges these concerns. “The fact that we’re fresh off the back of Brexit means that this is a particularly difficult time because the security concerns of the broader applications of quantum computing haven’t really been worked out yet.”
But Malcolm, like other scientists who the New Statesman spoke to, is keen to emphasise that there are plenty of potential applications, including in climate science, where the benefits of collaboration signficantly outweigh the security risks.
In partnership with Kai Bongs at Birmingham University, Ian Walmsley, an experimental physicist and the provost of Imperial College London, played a major role in developing the foundations of the EU’s quantum research, which largely focuses on medical and commercial applications.
Walmsley is frustrated that the UK may now be cut out of the scheme. “It’s not simply the intellectual capital we’ve put in; it’s the very strong partnerships we’ve developed over the years that have yielded benefit to the UK in terms of getting good people to work here, contribute their ideas and enable our reach and influence within the European programmes. So it is in that sense frustrating, but we’ve known for a while of course that the UK is leaving the EU so it’s not surprising that there will be some bumps in the road.”
Walmsley acknowledges it will be important for countries to have their own sovereign quantum capability, but that most of the work in the Horizon programme is at a pre-competitive stage. “There are good ways to protect intellectual property if either the EU or the UK has to protect its own strategic position. This is really about testing the ideas and proving them at this pre-competitive stage in a way that is going to move along this trajectory much more rapidly. It’s certainly true that a lot of countries are working on it and it’s certainly true that you don’t want to be left behind.”
Regardless of whether the UK is allowed to participate in the EU’s future quantum programmes, collaboration will continue between universities and tech companies across the Continent. But for Quantum Motion’s John Morton, the risk is not just that his company may be charged higher fees to access France’s microelectronics facility, but that “this kind of step escalates into – for want of a better phrase – a quantum arms race”.
“I think that would be a great shame and would mean the support we’re receiving from the UK government and the support that other organisations get from other member states will go less far because you’re putting up barriers to cooperation. It’s more about the missed opportunity and the signalling. It seems clear that such collaborations would be weaker without the structures of the Horizon Europe programme.”
A spokesperson for the European Commission said any limitation on third-states’ participation in Horizon Europe “will always be done in agreement with Member States in comitology and respecting our commitments under bilateral agreements. They will be exceptional, kept to the absolutely necessary minimum, and be duly justified.”
A spokesperson for the UK government’s business department said: “Earlier this month we announced an additional £250m in funding to support our participation in Horizon Europe, enabling the UK science and research sector to access to the largest collaborative funding scheme in the world.
“The UK has agreed to participate in the whole of the Horizon Europe programme, except the European Innovation Council Fund. However, the UK understands that in specific, exceptional cases the EU may exclude third country participants.”