Some of the world’s largest and most powerful technology companies —and some of the world’s largest and most powerful nations—are struggling to keep pace with a Toronto-based quantum computing start-up of fewer than 240 staff. Founded in 2016 by Australian-born entrepreneur Christian Weedbrook, who also holds a PhD in Quantum Information
Theory, Xanadu is the only company of its kind to have its work vetted and published in the science and technology world’s most esteemed research journal Nature—not just once or twice, but three times and counting.

“Based on that peer-reviewed, third-party validation, along with what was demonstrated in those results, [it’s safe to call Xanadu a global leader],” says Weedbrook from his home office in downtown Toronto, conveniently located across the street from Xanadu headquarters, near Yonge and College. “There’s been a lot of excitement in the last few months over what Google has done and what Microsoft has done, but if we had the PR department of those guys, this would be off the charts.”

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The long-term promise of quantum computer is profound. It may seem like hyperbole, but quantum computing has the potential to unlock solutions to some of the world’s most complex problems, so holding a possible key is potentially revolutionary. For the uninitiated, quantum computers differ from traditional computers in that they do not use bits that represent either 0 or 1, as classic computers do. Instead, they use qubits, which can represent 0, 1 or both at the same time through a concept called superposition. This allows quantum computers to perform complex calculations far faster than any existing computer, which, in turn, means this technology could transform fields like drug discovery, climate modelling and cryptography by solving problems that are currently too complex or time-consuming even for today’s most powerful machines.

This type of computing isn’t technically new. The theory behind quantum computing, which uses the principles of quantum mechanics to process information in fundamentally different ways from traditional computers, emerged as early as 1959 through the work of American physicist and Nobel Prize laureate Richard Feynman, followed by rapid theoretical advancements in the ‘80s and ’90s. But over the past five years, the world’s tech giants have turned their attention toward quantum computing in a big way, inspired by its future economic potential—and Canada has emerged as an unexpected global leader in this sector, driven by a robust ecosystem of research institutions, government support and innovative start-ups.

Weedbrook’s Xanadu exemplifies this leadership. With significant federal investment, including a CAD$40-million contribution from the Strategic Innovation Fund, Xanadu is developing the world’s first photonic-based (that is, one that uses photons, or individual particles of light), fault-tolerant quantum computer, making it the global front-runner. Canada’s commitment to quantum research was further cemented in 2023, when the government launched the National Quantum Strategy (NQS), which is backed by an investment of CAD$360 million and with the intent to not only advance quantum tech, but also create thousands of new jobs. This makes us an outlier. According to a 2024 backgrounder from the Council on Foreign Relations, globally, investment in quantum computing lags behind other emerging technologies. In fact, the NQS, which tops nearly CAD$1 billion in federal funding for quantum tech over the past 10 years, according to MITACS, makes Canada one of only 13 countries in the world with a national plan for quantum growth.

This support, combined with the country’s welcoming immigration policies and collaborative research culture, contrasts with the more restrictive climate in the U.S., especially as President Donald Trump cuts billions of federal dollars from research institutes and universities, restricting what can be studied and pushing out immigrants. It’s no wonder that Canada is increasingly becoming an attractive destination for top talent in the tech field.

That was certainly true for Weedbrook. After earning his PhD in 2009, he completed a six-month post-doctorate research fellowship at Boston’s Massachusetts Institute of Technology (MIT) before finding a more permanent home at the University of Toronto, due to what he describes as its unrivalled quantum tech program and “world-class talent.” He ended up spending nearly five years there, falling in love with the city in the process. In fact, Toronto’s diverse ecosystem has also been a significant pull for Weedbrook. While Canada has become a global magnet for third-culture talent overall, this is particularly evident in tech. In Toronto, more than half of start-ups have at least one foreign born founder, surpassing even Silicon Valley.

The results of this combination of investment, research culture and diversity are Volkswagen, Toyota, Rolls-Royce and BMW, who are seeking to apply those atomic-level computations to battery design. The field where the technology has the most promise, according to many experts, however, is pharmaceuticals. “If you want to cure something [or] you want to create a drug, your starting point is the traditional computer,” Weedbrook says, explaining that chemical compounds are first simulated in a digital environment. “Then you go and make the drug, and it goes from the computer to the real world. You go through clinical trials, and after 10 years, 90 per cent of them fail, and it costs CAD$1 [billion] or $2 billion.” With quantum computers, Weedbrook says there is little to no guesswork, as the laws that govern the machine’s operations are the same as those that govern the materials it’s simulating. “The systems that we’re trying to simulate—the molecules—they’re governed by quantum physics, so why not have a quantum clear: Xanadu’s first journal publication came in 2021, after the company created the world’s first programmable photon-based quantum circuit that can operate at room temperature, a major feat for a technology that was previously believed to function only in extreme temperatures.

“Our thesis from day one was, because you have to use light to connect, ‘Why not keep the whole computer as a light-based system?’” Weedbrook says. “If you’ve got two atoms, two electrons, it’s very challenging to connect them using photons. No one’s done that before—definitely not in a scalable way.”

Xanadu was highlighted in Nature again a year later for achieving “quantum supremacy,” after its quantum computer, Borealis, solved a complex math problem in two minutes that would have taken what was at the time the world’s fastest traditional supercomputer seven million years. That feat was previously only achieved by Google and by China’s University of Science and Technology.

Xanadu’s latest innovation is its most exciting yet. None of these, however, seem all that exciting in comparison as Weedbrook muses about Xanadu’s latest project, the subject of its most recent peer-reviewed paper and the image featured in his Microsoft Teams digital background: Aurora.

“Aurora has four server racks, each about seven feet tall, and the end vision is to actually build a quantum data centre in Toronto with thousands of server racks,” he says. “We only have four, but what we solved in this computer is the ability to scale out to thousands…Having them working together, networking and interconnecting using light, was always the big challenge, and the team at Xanadu showed how [it’s possible].”

While a commercial quantum computer is still decades away, at minimum, there are already practical applications for Xanadu’s technology. For example, the company has worked with auto manufacturers such as Volkswagen, Toyota, Rolls-Royce and BMW, who are seeking to apply those atomic-level computations to battery design.

The field where the technology has the most promise, according to many experts, however, is pharmaceuticals.

“If you want to cure something [or] you want to create a drug, your starting point is the traditional computer,” Weedbrook says, explaining that chemical compounds are first simulated in a digital environment. “Then you go and make the drug, and it goes from the computer to the real world. You go through clinical trials, and after 10 years, 90 per cent of them fail, and it costs CAD$1 [billion] or $2 billion.”

With quantum computers, Weedbrook says there is little to no guesswork, as the laws that govern the machine’s operations are the same as those that govern the materials it’s simulating.

“The systems that we’re trying to simulate—the molecules—they’re governed by quantum physics, so why not have a quantum [object] that you can simulate on?” he says.

“The idea with a quantum computer is that now you can simulate things so much better, you can have better candidates for drugs and materials, and, hopefully, flip it so there’s a 90 per cent success rate.”

Weedbrook believes our traditional approach to drug design, material sciences, computing and artificial intelligence could be completely reinvented by a quantum data centre, and Xanadu aspires to build the world’s first in 2029.

These days, tech innovation requires an entrepreneurial spirit. The path to founding and operating what is widely considered the world’s most advanced quantum computing start-up was not exactly what Weedbrook had in mind growing up about an hour outside of Brisbane, Australia. In fact, for much of his early life, he aspired to be a film director, despite earning his high school class’s highest grades in mathematics.

“There’s a race right now over
whose quantum [approach] is going to be purposeful, important or working. He has a better shot than most of winning this race”

Michael Hyatt, xanadu investor

“Not many people know this, but I did the first year [of film school] twice, and failed all subjects the first year, and failed everything except one subject the next year,” Weedbrook says.

After dropping out of film school shortly after, he spent three years pursuing what he describes as “embarrassing” attempts at entrepreneurship, including selling unused items from around the house at the local flea market or selling wheat-filled therapy bags prepared by his grandmother.

Five years after graduating from highschool, Weedbrook decided to take another crack at higher education, this time leaning into his natural abilities in math and physics.

“It wasn’t until I did my master’s that I learned more about quantum technologies,” he says. “The first foray into that was quantum teleportation, which sounded really cool, and then after that I heard
about quantum security and quantum computing and then decided to do my PhD in quantum computing.”

But the entrepreneurial spirit never left him. “In the back of my mind, as I’m going through the academic route, I was always thinking, Well, starting a business is something I’d love to do. I wonder whether the field where I’m contributing research—in quantum computing—is something that could be commercialized at some point?”

In 2014, he finally took the leap into entrepreneurship, launching a quantum security company called CipherQ.

“I was trying to raise money for that, and a lot of investors were saying, ‘Do you know anything about quantum computing? Because we would rather invest in quantum computing than quantum security,’” he says. “You can think of [investors] as being a customer, and the customers were saying, ‘We actually want this.’”

In 2016, Weedbrook launched his quantum computing start-up, Xanadu, and abandoned CipherQ soon after.

“In the early days, it was, ‘Can we just get enough money to survive and hire some people?’ That was the challenge,” he says. “I wanted to stay in Toronto and give it a go doing a start-up, and Toronto is great, because there’s a lot of incubators, funding has increased and there’s a lot more venture capital here.”

Weedbrook says resources such as the University of Toronto’s Creative Destruction Lab, an incubator that Xanadu joined in 2016, helped the company survive those early days, despite not generating revenue.

“He’s a very, very smart guy, and he had the very classic BHAG—the ‘big, hairy, audacious goal,’” says serial investor and entrepreneur Michael Hyatt, who was a founding partner of the Creative Destruction Lab and one of Xanadu’s earliest investors. “Investing in him was easy, because he’s so smart, and he had what I would call ‘a snowball’s chance in hell.’”

Hyatt adds that he was not only impressed by Weedbrook’s credentials and ambition, but also his novel approach to building quantum computers using photon, or lightbased, technology.

“There’s a race right now around the planet over whose quantum [approach] is going to be generally purposeful, important or working, and no one’s quite achieved the panacea,” he explains, adding that competitors range from Google, Amazon, Microsoft and IBM to other start-ups in Korea, China, Australia and elsewhere around the world. “He has a better shot than most of winning this race, I would put it that way.”

After graduating from the incubator program in 2017, Weedbrook describes a recurring cycle of setting an ambitious goal—such as those highlighted in Nature, or creating his quantum operating system, PennyLane—raising capital based on that achievement, using that capital to hire more staff and directing the new hires’ attention toward the next goal.

“At some point, I started getting frequent phone calls from Christian, because he would go down the list of my PhD students and ask, ‘Now that they’ve completed [their studies], is this one any good?’” says Norbert Lütkenhaus, the executive director at Waterloo’s Institute for Quantum Computing (IQC) and a physics professor at the University of Waterloo. “If you look through the leadership of Xanadu, you’ll find some of my former students working there.”

Lütkenhaus adds that it’s a mutually beneficial relationship, as it gives graduates of a relatively niche and highly technical field a career that allows them to apply their education.

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Despite Canada’s investment, quantum computing remains a long game. He, like Hyatt and Weedbrook, believes the opportunities that will result from quantum computing—once made accessible and
deployed on a wide scale—are almost infinite; but he also cautions that the path to achieving it is long and far from certain.

“We have not even fully comprehended yet what quantum computers can be doing,” Lütkenhaus says. “We know the advantages, we see some path to it, but everything is still in flux and shifting, and I think we need to be clear that coming to a quantum computer that can indeed fully leverage all the things we know it should be able to do in principle is not coming in five years; it’s a long road.”

That uncertain journey has also made fundraising a constant challenge. Xanadu, and other start-ups like it, could become the next Microsoft or IBM, or fade away into the history books, and it could take decades and billions of dollars before that fate is clear.

But investment is incredibly important—and not just from a business perspective. The geopolitical implications of quantum computing are profound. As the Council on Foreign Relations notes, “if quantum computing makes standard encryption obsolete, governments will have to contend with significant military and economic disruptions, [a possibility that] has come to be known as ‘Q-day.’’ …In a Q-day scenario, hackers would more easily be able to break through defensive barriers to access critical systems, such as energy grids and nuclear reactors.”

The American intelligence community says it doesn’t expect to contend with quantum computing in cryptography until the 2030s, and skeptics believe even that is ambitious, but some national security experts do believe these advancements could come much sooner than that. It’s clear, then, that even the possibility of quantum cryptography is as pressing a motivating factor as the pure business potential of this technology. Thus far, Xanadu has raised US$250 million from private investors and received an additional US$40 million from the Canadian and American governments. It sounds like a lot of money, but the sum pales in comparison to the kinds of capital its tech behemoth competitors can access.

Weedbrook, however, isn’t dismayed by the size of the task at hand (namely, reinventing the field of computing at an atomic level), the seemingly infinite war chests of his competitors or the long road that lies between Xanadu’s current state and its stated goal of building “quantum computers that are useful and available to people everywhere.”

All he sees are the next ambitious but achievable goals, the next peer-reviewed journal article (which has already been accepted, though the content has not yet been made public), the next funding round and the next group of world-class hires.

Through that lens, achieving what is referred to as “quantum commercial supremacy” and delivering what he believes will be quantum computing’s “ChatGPT moment” aren’t necessarily all that far away.

“We’re still on track for 2029 to have the world’s first quantum data centres here in Canada,” Weedbrook says. “We have a great team, we’ve shown some tremendous results—including the Aurora computer—and we have a really high probability of actually being one of the leaders in this field.” For more thought-provoking stories and exclusive content, subscribe to 3 magazine’s print and digital editions today!