Q-CTRL: Building foundations for a stable Quantum revolution

“Quantum technology will be as transformational in the 21st Century as harnessing electricity was in the 19th,” says Professor Michael Biercuk, founder and CEO of Sydney-based quantum control company, Q-CTRL, in the company’s introductory homepage video. It’s by no means a controversial statement given the potential power of the technology. When I ask Biercuk to expand on the idea we immediately get into substantive historical parallels – that the modern era has been powered by the discovery and the harnessing of electricity as a resource, and we’ve recently started learning how to harness quantum physics in a similar way.  But the conversation quickly arrives at the subject of quantum hype: the vested interests, techno-evangelists and reactionaries who read and feed the myth that a breakthrough in quantum technology is coming any day now, and any country, company or investor not on board the train today is going to be left irretrievably behind tomorrow. A century is a long time and quantum’s place in this one will be transformational, but buyer beware the throng of ‘quantum experts’ promising an overnight revolution.

“Timelines are the biggest bugbear,” Biercuk says. “The reality is that quantum technology is the deepest of deep technology R&D fields. Those of us who are embedded in this field are in large part saying that we believe that in the next five-to-eight years, we will see the first commercially relevant use of a quantum computer where there is some advantage over a classical solution: maybe it’s cheaper, maybe it’s faster. It’s still probably 30+ years away to a useful factoring engine. This is my informed, professional opinion, and it’s relatively consistent with my peers. But you now see an expansion of non-technical analysts commenting in the literature that in the next two years we’re going to have useful factoring engines, so we need to have a replacement for RSA now. That’s just not true.”

Biercuk has long experience across the spectrum of quantum technology interests. At the government level he worked at both the Defense Advanced Research Projects Agency (DARPA) and the National Institute of Standards and Technology (NIST) in the US. In 2010, he relocated to Australia to take up a faculty position at the University of Sydney. Finally in 2017 he founded and took on his current position as CEO of Q-CTRL, a company which - as well as offering quantum modelling software packages to beginners and experts - builds stability into quantum technologies at the hardware level, protecting against noise and interference that would potentially compromise the output of a given quantum device.

“This is something that I’ve built my career around,” says Biercuk. “Error and noise, these are the Achilles heels of quantum computing; there is extraordinary fragility of quantum computing hardware to its environment, which leads to errors in algorithms. Addressing this issue has been the source of almost all the research activity in the field for a good number of years. My team and others around the world have specialized in how to deal with this by leveraging insights from a field that is traditionally called ‘control engineering’, the discipline that makes pretty much all modern technology work.”

“In the context of quantum mechanics or quantum devices, we were really learning how to put quantum systems to work in applications by making them robust against error – building a field now called quantum control.  And all of the work that we had done in my academic lab in developing these foundational techniques became the core of the technology that we started to build at Q-CTRL.”

Even after years of working at the center of one of the biggest challenges in quantum computing and technology, before founding Q-CTRL just under two years ago, Biercuk was still strongly advising caution to would-be investors. Despite the years at DARPA, NIST and the more than half-decade at the University of Sydney, it wasn’t until 2017 that he took that expertise and pulled the trigger on a personal entrepreneurial move in quantum control.

“Around 2015, we started to see an uptick in investment from the industrial sector, starting with big tech oligopolies and then the emergence of start-ups in quantum computing,” he says. “I had many, many investors coming to me as an academic asking my opinion on how to invest in the field, and the uniform response I gave to everybody was: ‘It’s too early’. And I stood by that until I went to an event in Munich hosted by a venture capital firm, bringing together more of what you might call the ‘application-minded’ people in the research community, from both academia and industry. I emerged from that event with the view that, ‘The time is now’. It was now-or-never to try something commercial in quantum technology. I had ideas I’d been kicking around and when I returned I approached a couple of investors with whom I’d been interacting and said, ‘Now is the time - let’s do this’. And so we did. That meeting was July 2017 and Q-CTRL was formed formally with its first round of investment on November 2^nd 2017.”

That relatively slow transition from government work and academia into private business, especially compared with the stories of some of quantum’s louder entrepreneurs, was spent building up deep expertise. When Biercuk talks about the potential transformative effects of quantum technologies - whether that’s in materials research for superconducting power grids or factoring engines’ impacts on far-future cryptography - Biercuk doesn’t downplay the long-term impacts. But his focus - Q-CTRL’s focus - is grounded in what will be practically possible in the near future, rather than trying to build solutions “for machines that don’t really exist yet.” and which require longer-term speculation.

As a concrete example within the technical subfield dealing with error in quantum computers, he makes the comparison between efforts developing the mathematics of quantum error correction (QEC) codes and Q-CTRL’s work at the physical, engineering level. “As essential as quantum error correction is in the long term, the latter," Biercuk says, “feels more real at this point”.

“In the quantum computer stack, error correction is a high-level algorithm that you run to detect and remedy any computational errors, and is likely necessary when we consider building very large machines in the future.  Our efforts are complementary;  at the physical layer we apply control engineering techniques to make the hardware less error prone.  That improves hardware performance today, but also makes quantum error correction work better in the long term.” Biercuk explains.

“In a simple analogy, imagine trying to balance a meter stick on your finger; if it falls, that’s an unrecoverable error or hardware failure which we’re trying to prevent.The quantum control techniques we use are a little bit like trying to balance the meter stick by dynamically moving your finger around to keep it upright. It works pretty well overall. By contrast, Quantum Error Correction instead suggests you “duplicate” or “encode” your meter stick into a whole room full of people with meter sticks on their fingers. The more unstable your meter stick, the more extra people you need.  Then if you’ve made enough “copies,” one falling over isn’t the end of the world; the QEC algorithm can look at the whole room, identify when one falls over, and restore it to its upright position again without disturbing the delicate quantum information.  It’s an important idea in principle but in practice you end up dedicating all of those additional meter sticks just to the task of identifying when one falls over, instead of, well, whatever you really wanted to do with your meter stick.”

Until QEC is fully demonstrated, physical-layer stabilization offers a concrete way to make quantum computers more useful.  Ultimately, it also helps improve the efficiency of QEC by reducing the resources needed for QEC – the number of “meter sticks” in our example.  “At Q-CTRL we’ve taken an engineering perspective seeking to unify what have historically been very separate areas of research in the field.  QEC, after all, is just another form of quantum control (closed-loop feedback to be specific).”

Efficiently creating stability for quantum devices at the hardware level has made Q-CTRL appealing to investors - and the company will soon expand its operations from Sydney to offices in the US. But again, when it comes to the future of the industry as a whole, Biercuk is cognizant of governments, companies and spokespeople overpromising and the impact that failed expectations could have across the field.

“Irrational exuberance about quantum technology and quantum computing has led to unsophisticated investors getting heavily involved - and that’s dangerous because it really destabilizes the field. If you have people who think that quantum computers are coming on the same time horizon as mobile application development, you have a fundamental problem. I do think that we have seen some of that and we need to make sure that we keep expectations aligned with reality.  If investors turn on the field because they never really understood the timelines for building this technology in the first place, we will all suffer.”

While that disconnect between reality and expectation already creates problems for business, Biercuk identifies a far more potentially pernicious problem further down the road. Inflating the near-term potential of quantum technology confuses investors and the public - if a slew of newspaper headlines announce a relatively small development in such-and-such a field of quantum as a panacea that will change the world by Christmas, that same public (and even more so those investors) will be rightfully disappointed when it doesn’t. But promises along those lines aren’t uncommon when it comes to quantum technologies, and while some companies fail and investors get stung, the industry as a whole keeps moving forward.

However, there is one outlying area in which overstating the near-term potential of quantum technology could have truly disastrous knock-on effects: national security. When policymakers are fed bad information or begin repeating poorly-informed soundbites on ‘quantum threats’, the problem hops neatly from overpromising to catastrophizing.

“The geopolitical tensions - between the US and China in particular - are really, potentially detrimental,” Biercuk says. “Western spy agencies and defense think tanks... they appear terrified of China and China’s interest in quantum computing. So, right now there are moves afoot to try to export-control many areas of quantum computing. And unfortunately, as part of a global industry, those export controls could absolutely decimate us.”

“The problem is largely based around think tanks and policy analysts who listen to Chinese government proclamations or read popular press descriptions of what quantum computers without real understanding, and then make suggestions about how we need to control these technologies. Some of the most egregious cases are people who conflate this idea of quantum supremacy with a factoring engine and say, ‘If Google is going to reach quantum supremacy next year we immediately need export controls to prevent this getting into Chinese hands.’ That’s just… That’s just not fact-based. But with the rise in prominence of these hawkish elements in the defense establishment, their voices - as ill-informed as they may be - become loud and listened to. That’s very dangerous for our whole industry.”

Biercuk isn’t blind to the strategic potential of quantum technologies. As is or has been true in practically all areas of high tech, the military is a key driver of investment and advancement in quantum computing, including much of Biercuk’s academic research. Whatever quantum’s other promises, defense dollars pay for defense products. It’s also true that Western militaries (and the US in particular) are disproportionately dependent on the transfer of encrypted information to fight wars. Technologies that jeopardize those communications networks are potentially existential threats to the countries that depend on them.

But ‘potential’ is the key word. Quantum technologies have clear potential as offensive and defensive tools, which is why closing the gap between quantum technology as it exists and quantum technology as it is reported and promoted is critical. Having enemies at the gate is bad. Having a coach-load of collaborating researchers at the gate and mistaking them for enemies is potentially worse.

“Everything we do is global: it’s a completely, globally engaged R&D effort,” says Biercuk. “But so much of what we do is still scientific discovery, as much as it is applied science or engineering. We’re learning new things about how to manipulate the quantum world and new ways to put quantum resources to use for computation. These are things that we publish. And because we publish them openly it doesn’t really make any sense to start trying to export control them.

“If you want to introduce export controls, those export controls need to focus on defense-relevant quantum computing.  And right now the only defense-relevant quantum computing application that anybody knows about, at least in the public sphere, is decryption. The time horizon to realizing a suitable machine is probably more than 30 years.  It doesn’t make any sense at all to try to control a nascent technology that, right now, is 100% civilian simply for fear that it may turn into something else decades down the road. Scientific information is not easily contained, and the downsides of limiting commercial development and scientific exchange can be catastrophic.”

Ever the pragmatist, Biercuk engages in this policy discourse, but keeps Q-CTRL focused on the practical challenges and opportunities that quantum computing faces today, rather than theoretical problems which may appear tomorrow. It’s such real-world problem solving that will help enable a sustainable quantum revolution.