Modifying $n$-qubit controlled-$ZX$ gate to be $n$-qubit Toffoli gate

Jian Leng; Fan Yang; Xiang-Bin Wang

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arXiv · 2305.15018

Modifying $n$-qubit controlled-$ZX$ gate to be $n$-qubit Toffoli gate

Jian Leng·Fan Yang·Xiang-Bin Wang

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Abstract

The decomposition for controlled-$ZX$ gate in [Phys. Rev. A, 87, 062318 (2013)] has a shallow circuit depth $8n-20$ with no ancilla. Here we modify this decomposition to decompose $n$-qubit Toffoli gate with only $2n-3$ additional single-qubit gates. The circuit depth is unchanged and no ancilla is needed. We explicitly show that the circuit after decomposition can be easily constructed in present physical systems.

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Jian Leng, Fan Yang, Xiang-Bin Wang. 2023-05-24. Modifying $n$-qubit controlled-$ZX$ gate to be $n$-qubit Toffoli gate. https://arxiv.org/abs/2305.15018

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