One of the many bright spots of the quantum computing industry is its ability to mobilize some of the most brilliant minds across both academia and industry. Developing quantum computers requires a multidisciplinary team of physicists, computer scientists, engineers, mathematicians, computer architects, and more. For IonQ Principal Researcher Nicolas Delfosse, his entry into the field came via pure mathematics. Yet, his ongoing research in error correction will now inform the design and development of highly advanced, next-generation quantum computers – a process that is well underway here at IonQ.
Delfosse, who holds a PhD in Mathematics from the University of Bordeaux in southern France, embarked on a unique journey early in his career that eventually took him from the classroom to the business world. For his doctorate, he focused on quantum error correction, but at a time when quantum computing was mostly academic and still niche. He then took his postdoc studies to Polytechnique in Paris, and later to the physics department of Sherbrooke University in Québec. There, he gradually learned and adopted the “language” of physics, which is now so integral to his day-to-day work. He later moved to Caltech and, subsequently, the job market.
By 2017, momentum was building around quantum computers and their practical applications. Recognizing its potential, Delfosse joined Microsoft’s research team, and was an integral part of its quantum error-correction work. He addressed practical research problems alongside more existential, longer-term questions like how to power more robust machines.
He joined IonQ in late-2023 with the intention of working more closely with qubits – and cited IonQ’s high-quality qubits and flexible gate set as part of that reasoning. Delfosse also praised IonQ’s visionary leadership team and the “impressive” rate of innovation and product roadmap.
“We have beautiful math problems to solve and we are building a new generation of quantum computers. There is nothing more exciting,” Delfosse says.
He now stands ready to help build and refine large-scale quantum computers – particularly fault-tolerant systems.
“The primary challenge for the community is ‘noise.’ Without error correction, a fault occurring during a computation rapidly spreads to all the qubits, making the final result useless,” Delfosse explains. “To run algorithms on many qubits, we need to transition from small, noisy devices to large-scale, fault-tolerant quantum computers, where error correction is used to improve the computation. The main goal of my research is designing error correction codes adapted to our devices.”
A modular quantum computer – made with modules of high-quality qubits connected through optical interconnects – offers the flexibility needed to handle the aforementioned challenges. As both Delfosse and our wider team acknowledge, this presents another IonQ strength: We are currently hitting key technical milestones with interconnect technology to enable quantum networking between and within quantum computers.
The nature of Delfosse’s work frequently gets him thinking about the industry’s bright future, particularly a “less noisy” one where quantum systems have achieved true “advantage” (the point at which the devices exceed the computational power of classical computers).
“We need to keep building bridges between the different disciplines so that every stakeholder can work together and build this large-scale, fault-tolerant quantum computer,” he adds.
Outside of his daily research, Delfosse, a Seattle resident, is frequently invited to give lectures on quantum computing for the nonprofit institution, the Northwest Academy of Sciences. He’s also an avid fan of science fiction, particularly the works of prolific author Isaac Asimov, best known for his “Foundation” trilogy. His current obsession: Dennis E. Taylor’s “Bobiverse” sci-fi series, in which an engineer revived as artificial intelligence is dispatched to explore the universe. Delfosse is also a boulderer and runner, and in 2023 completed his first marathon.