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arXiv · 2203.11882

Linear-depth quantum circuits for multiqubit controlled gates

Adenilton J. da Silva·Daniel K. Park
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Abstract

Quantum circuit depth minimization is critical for practical applications of circuit-based quantum computation. In this work, we present a systematic procedure to decompose multiqubit controlled unitary gates, which is essential in many quantum algorithms, to controlled-NOT and single-qubit gates with which the quantum circuit depth only increases linearly with the number of control qubits. Our algorithm does not require any ancillary qubits and achieves a quadratic reduction of the circuit depth against known methods. We show the advantage of our algorithm with proof-of-principle experiments on the IBM quantum cloud platform.

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Adenilton J. da Silva, Daniel K. Park. 2022-03-22. Linear-depth quantum circuits for multiqubit controlled gates. https://doi.org/10.1103/physreva.106.042602

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