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arXiv · 1207.2944

Feedback control of a solid-state qubit using high-fidelity projective measurement

D. Ristè·C. C. Bultink·K. W. Lehnert·L. DiCarlo
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Abstract

We demonstrate feedback control of a superconducting transmon qubit using discrete, projective measurement and conditional coherent driving. Feedback realizes a fast and deterministic qubit reset to a target state with 2.4% error averaged over input superposition states, and cooling of the transmon from 16% spurious excitation to 3%. This closed-loop qubit control is necessary for measurement-based protocols such as quantum error correction and teleportation.

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D. Ristè, C. C. Bultink, K. W. Lehnert, L. DiCarlo. 2012-07-12. Feedback control of a solid-state qubit using high-fidelity projective measurement. https://doi.org/10.1103/physrevlett.109.240502

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