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arXiv · 1910.01175

A note on the entangling properties of the C-SIGN and related quantum gates

Stephen A. Fenner
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Abstract

We show that any essential application of an $n$-qubit C-SIGN or related quantum gate $G$ leaves its qubits everywhere entangled, provided they were not everywhere entangled to begin with. By ``essential'' we mean roughly that $G$ is not equivalent to a similar gate of smaller arity (or to the identity) when applied to the same input state. By ``everywhere entangled'' we mean that the state is not separable with respect to any bipartition of the qubits.

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Stephen A. Fenner. 2019-10-02. A note on the entangling properties of the C-SIGN and related quantum gates. https://arxiv.org/abs/1910.01175

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