Where is Quantum Computing Heading Next?

At CES 2019, IBM revealed their first commercial quantum computer, and the technology world took notice. This is not even the company’s first foray into quantum computing, but it certainly is the one which resonated loudest. But what exactly is behind the inch-thick glass of IBM’s wondrous machine?

Quantum computing is increasingly becoming a more ordinary topic in tech. This is the consequence of nearly four decades of non-stop advances in mathematics, computer science, engineering, and chemistry. All this allowed quantum technologies to leap out of the peace and quiet of academic labs and launch their quest to tackle computing’s most challenging problems.

Long-awaited future

Here is the gist of it: quantum computers, no matter how big or powerful they get in the years to come, will only ever be great at solving certain computational problems. Therefore, it is easy to realize that the true power of these machines could be unleashed by coupling them to a powerful super-computer, just like the ones found in any scientific lab around the world.

However, quantum computers are not ordinary machines: they utilize the principles of quantum mechanics (most importantly, superposition and entanglement) to perform certain computing operations exponentially faster than classical computing machines. Quantum computers are bound to revolutionize the areas of technology where such problems are encountered: most notably encryption, pattern-matching and optimization.

Starting in the late 80s, for long years quantum computing was exclusively the topic of academic research, with little perspective to be practically viable any time soon. In the 90s, some important algorithms were discovered, which for example promised that a quantum computer, if ever developed, would render the widely used credit card encryption (RSA) obsolete. However, engineering advances lagged behind theoretical discoveries and the prospects of developing such hardware appeared bleak. The difficulty comes from the need to breed and manipulate qubits — the quantum counterparts of bits — out of elementary particles, which proved to be a cumbersome task. However, with advances in material science in the 00s, primitive versions of a quantum computer became viable, and the race to build a functioning prototype was on.

Out of the lab

The first to develop a quantum computing device was the Canadian startup D-Wave, who released their first machine in 2011. This generated even further interest, and soon other players joined the space too. Google hired an entire physics department (on top of buying each new machine by D-Wave), Microsoft invested billions into their own quantum computing department, Alibaba launched a program to develop cloud quantum computing, and so on. IBM also joined the race, first releasing a 5-qubit quantum computing accessible on their website, then upgrading it to 16 qubits, and now releasing a fully optimised solution for businesses. What’s the difference between each company’s approach? They all use different physical media to create and store the qubits which are necessary for the machine’s operation.

There are ongoing efforts to develop large-scale networks which rely on quantum encryption (while Geneva’s local elections have already been relying on this technology since 2007). Governments are leading the way in defense applications, with China pioneering quantum-encrypted space transmission.

On the software side, startups like Cambridge Quantum Computing are working hard to develop software that will power the quantum hardware, and will allow developers to tackle computing problems which seem intractable with contemporary machines.

High in the clouds

Quantum computing’s future is certainly bright, but where does that leave the everyday user without access to multimillion-dollar hardware? IBM’s machine, like the others by Google and D-Wave, require a lot of power and cooling — the qubits need to be kept at near-absolute zero. It appears that initially, only large businesses would be able to enjoy the spoils of this new technology — hedge funds, investment banks, pharmaceutical companies and defense contractors could easily shell out the millions necessary to build and maintain such machines. However, as the technology becomes more affordable and powerful, providers will launch cloud quantum service for individual users — then everyone with an internet connection will be able to reap the benefits of several decades of technological advancements.

The author Deyan Mihaylov has been part of the UK startup Cambridge Quantum Computing since their very beginning. He is currently also a post-doctoral assistant at the University of Cambridge, where he researches and teaches theoretical physics.