A quantum computer called Helios has topped 99.9% fidelity rates for both one- and two-qubit operations, according to Phys.org.
The results were announced by a public-private partnership in the Mountain West, Phys.org reports. The announcement frames the milestone as steady progress toward a U.S. Department of Energy goal: building fault-tolerant quantum computers, the kind of large, reliable systems the field has long been working toward.
Fidelity is a measure of how accurately a quantum computer carries out its basic operations. "Qubits" are the building blocks of these machines, and operations on one or two qubits at a time are the elementary steps from which larger calculations are assembled. The higher the fidelity, the fewer errors creep into each step. Crossing 99.9% on both single- and two-qubit operations is a closely watched benchmark because errors are the central obstacle standing between today's experimental machines and practical, large-scale quantum computing.
The sources available here do not name the specific institutions or companies behind the partnership beyond locating it in the Mountain West, nor do they detail the underlying hardware technology or independent verification of the figures.
Why it matters: error rates are the main barrier to useful quantum computers, so a credible report of 99.9% fidelity on the most basic operations is a meaningful marker on the long road toward machines that could one day tackle problems beyond the reach of conventional computers.