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IPFS News Link • Science, Medicine and Technology

Atom Computing First to Exceed 1,000 Qubits With 1180 Qubit Neutral Atom Quantum Computer

•, by Brian Wang

This is the first time a company has crossed the 1,000-qubit threshold for a universal gate-based system, planned for release next year. It marks an industry milestone toward fault-tolerant quantum computers capable of solving large-scale problems.

The new 1,225-qubit quantum computer uses ytterbium-171 atoms to create its qubits.

PRX Quantum – Repetitive Readout and Real-Time Control of Nuclear Spin Qubits in 171 Yb Atoms

We demonstrate high-fidelity repetitive measurements of nuclear spin qubits in an array of neutral ytterbium-171 (171Yb) atoms. We show that the qubit state can be measured with a spin-flip probability of 0.004 for a single tweezer and 0.012 averaged over the array. This is accomplished by high cyclicity of one of the nuclear spin qubit states with an optically excited state under a magnetic field of B=58 G, resulting in a spin-flip probability of approximately 10^−5 per scattered photon during fluorescence readout. The performance improves further. The state discrimination fidelity is 0.993 with a state-averaged readout survival of 0.994, limited by off-resonant scattering to dark states. We combine our measurement technique with high-contrast rotations of the nuclear spin qubit via an ac magnetic field to explore two paradigmatic scenarios, including the noncommutativity of measurements in orthogonal bases, and the quantum Zeno mechanism in which measurements "freeze" coherent evolution. Finally, they employ real-time feedforward to repetitively and deterministically prepare the qubit. These capabilities constitute an important step towards adaptive quantum circuits with atom arrays.