On the ISC exhibition show floor, you’ll see many examples of progress in advanced computing, namely faster processors, denser systems, and sophisticated cooling technologies. But every so often, something different appears that is not just an incremental improvement, but a fundamentally different approach to solving supercomputing’s hardest problems.
We think one of those moments may be found this year at the booth of a company called Alice & Bob (G40, Hall H).
Founded in Paris in 2020 by physicists Théau Peronnin and Raphael Lescanne, Alice & Bob is becoming one of Europe’s most talked-about quantum computing startups. With €130 million in funding and 180 employees, the company is building quantum computers that can operate reliably enough to perform useful work – not just in laboratory conditions, but in real-world computing environments.
Why This Distinction Matters
For decades, the field has been held back by a single, stubborn challenge: errors, or to be more specific, error correction. Qubits, the building blocks of quantum computers, are extraordinarily fragile. The slightest disturbance caused by thermal noise, electromagnetic interference, or imperfections in hardware can disrupt calculations. Correcting those errors is possible, but at an enormous cost. Conventional approaches may require thousands, or even millions, of physical qubits to produce a single reliable logical qubit.
Alice & Bob’s approach challenges that equation at its foundation. The company’s technology is built around the “cat qubit,” named after Schrödinger’s famous thought experiment in quantum mechanics. Unlike conventional designs that focus heavily on correcting errors after they occur, cat qubits are engineered to suppress a certain type of errors from the outset. Specifically, the cat qubit is able to significantly reduce the number of “bit-flip” errors that naturally occur in conventional qubits. By reducing error rates at the hardware level, the architecture could dramatically lower the number of physical qubits required to build useful quantum systems.
For those of us in high performance computing, this is not just a scientific curiosity; it is a question of feasibility.
If quantum computing is to become a practical tool alongside classical supercomputers, it must be engineered into systems that are scalable, reliable, and economically viable. Hardware-efficient approaches like Alice & Bob’s could make that transition significantly more achievable.
The company’s rapid growth reflects the urgency of this challenge. With operations in Paris and Boston and an expanding engineering team, Alice & Bob is positioning itself as a contender in the race to build fault-tolerant quantum processors. Its work is not happening in isolation, but as part of a broader shift toward hybrid computing environments where quantum accelerators may one day complement traditional processors.
For HPC center directors, system architects, and researchers thinking about the future of computing infrastructure, Alice & Bob represents something important: a company focused on solving the practical constraints that have so far limited the usefulness of quantum computing.
The cat qubit is not a finished story. But it is a credible attempt to overcome one of quantum computing’s most persistent barriers.
And that alone makes Alice & Bob one of the most interesting companies to watch at ISC this year.
