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arXiv · 2310.14974

Linear decomposition of approximate multi-controlled single qubit gates

Jefferson D. S. Silva·Thiago Melo D. Azevedo·Israel F. Araujo·Adenilton J. da Silva
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Abstract

We provide a method for compiling approximate multi-controlled single qubit gates into quantum circuits without ancilla qubits. The total number of elementary gates to decompose an n-qubit multi-controlled gate is proportional to 32n, and the previous best approximate approach without auxiliary qubits requires 32nk elementary operations, where k is a function that depends on the error threshold. The proposed decomposition depends on an optimization technique that minimizes the CNOT gate count for multi-target and multi-controlled CNOT and SU(2) gates. Computational experiments show the reduction in the number of CNOT gates to apply multi-controlled U(2) gates. As multi-controlled single-qubit gates serve as fundamental components of quantum algorithms, the proposed decomposition offers a comprehensive solution that can significantly decrease the count of elementary operations employed in quantum computing applications.

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Jefferson D. S. Silva, Thiago Melo D. Azevedo, Israel F. Araujo, Adenilton J. da Silva. 2023-10-23. Linear decomposition of approximate multi-controlled single qubit gates. https://doi.org/10.1109/tcad.2024.3471905

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