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arXiv · 1510.00121

Method for quantum-jump continuous-time quantum error correction

Abstract

Continuous-time quantum error correction (CTQEC) is a technique for protecting quantum information against decoherence, where both the decoherence and error correction processes are considered continuous in time. Given any [[n,k,d]] quantum stabilizer code, we formulate a class of protocols to implement CTQEC, involving weak coherent measurements and weak unitary corrections. Under this formalism, we show that the minimal required size of the ancillary system is n-k+1 qubits, and we propose one scheme that meets this minimal requirement. Furthermore, we compare our method with other known schemes, and show that a particular measure of performance described in this paper is better when using our method.

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BibTeXRIS

Kung-Chuan Hsu, Todd A. Brun. 2016-02-18. Method for quantum-jump continuous-time quantum error correction. https://doi.org/10.1103/physreva.93.022321

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