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Correcting low-frequency noise with continuous measurement

L. Tian
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Abstract

Low-frequency noise presents a serious source of decoherence in solid-state qubits. When combined with a continuous weak measurement of the eigenstates, the low-frequency noise induces a second-order relaxation between the qubit states. Here we show that the relaxation provides a unique approach to calibrate the low-frequency noise in the time-domain. By encoding one qubit with two physical qubits that are alternatively calibrated, quantum logic gates with high fidelity can be performed.

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L. Tian. 2006-06-19. Correcting low-frequency noise with continuous measurement. https://doi.org/10.1103/physrevlett.98.153602

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