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Measuring the parity of an $N$-qubit state

B. Zeng·D. L. Zhou·L. You
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Abstract

We present a scheme for a projective measurement of the parity operator $P_z=\prod_{i=1}^N σ_z^{(i)}$ of $N$-qubits. Our protocol uses a single ancillary qubit, or a probe qubit, and involves manipulations of the total spin of the $N$ qubits without requiring individual addressing. We illustrate our protocol in terms of an experimental implementation with atomic ions in a two-zone linear Paul trap, and further discuss its extensions to several more general cases.

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B. Zeng, D. L. Zhou, L. You. 2005-08-05. Measuring the parity of an $N$-qubit state. https://doi.org/10.1103/physrevlett.95.110502

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