Physicists have assembled the first complete set of quantum logic operations built entirely from non-Abelian anyons, exotic quasiparticles long considered one of the most promising — and most stubborn — routes to a fault-tolerant quantum computer. A team spanning Harvard University, the University of Chicago's Pritzker School of Molecular Engineering, Stony Brook University and quantum computing firm Quantinuum reported the result this month in Nature, describing the first demonstration that these particles can support universal quantum computation on real hardware rather than only on paper.
The experiment ran on Quantinuum's H2 trapped-ion processor, where researchers entangled 54 qubits to construct anyons obeying "S3" symmetry, the set of rotations and mirror-flips of an equilateral triangle. Instead of ordinary two-level qubits, the information was stored in "topological qutrits," units holding three quantum levels at once. The team then demonstrated three operations: an entangling gate produced by braiding, or physically swapping anyons around one another, and two measurement techniques based on "fusing" pairs of anyons together. Combined, those operations are enough, in principle, to run any quantum computation.
Braiding alone wasn't enough
Non-Abelian anyons are quasiparticles that can only exist in two-dimensional systems and behave unlike any fundamental particle: swapping two of them in different orders leaves the system in genuinely different quantum states, a kind of built-in memory that theorists have wanted to exploit since Caltech's Carlos Mochon showed in 2003 that certain anyon models could mathematically support universal computing. Earlier hardware demonstrations, including a 2024 experiment using a different symmetry group, showed braiding alone could entangle qubits but could not complete a universal gate set. The new work's key move was pairing braiding with fusion-based measurements to fill that gap.
We demonstrated a so-called universal gate set — you can do any quantum computation you might want to do.
Ruben Verresen, University of Chicago Pritzker School of Molecular Engineering
Fault-tolerant computations can in principle be done without resorting to magic state distillation.
Henrik Dreyer, Quantinuum
Magic state distillation is a resource-intensive technique that today's quantum computers typically rely on to correct errors, so a path that avoids it could ease one of the field's biggest engineering bottlenecks. Researchers described the anyon-based approach as a "dark horse" among competing strategies for fault tolerance, according to ScienceDaily, since it had lagged better-funded approaches until this result.
What's next
The next step, researchers said, is combining this anyon-based scheme with quantum error correction to test whether it can scale into a practical machine. The team plans to push beyond 54 qubits and try other symmetry groups to find the best balance of computational power and physical simplicity. Neither Quantinuum nor its academic partners have set a timeline for a device built on the approach, but the demonstration stands as one of the clearest hardware proofs yet that anyons, once a largely theoretical curiosity, can do real computational work.