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arXiv · 2408.07964

A Quantum Approximate Optimization Method For Finding Hadamard Matrices

Andriyan Bayu Suksmono
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Abstract

Finding a Hadamard matrix of a specific order using a quantum computer can lead to a demonstration of practical quantum advantage. Earlier efforts using a quantum annealer were impeded by the limitations of the present quantum resource and its capability to implement high order interaction terms, which for an $M$-order matrix will grow by $O(M^2)$. In this paper, we propose a novel qubit-efficient method by implementing the Hadamard matrix searching algorithm on a gate-based quantum computer. We achieve this by employing the Quantum Approximate Optimization Algorithm (QAOA). Since high order interaction terms that are implemented on a gate-based quantum computer do not need ancillary qubits, the proposed method reduces the required number of qubits into $O(M)$. We present the formulation of the method, construction of corresponding quantum circuits, and experiment results in both a quantum simulator and a real gate-based quantum computer.

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Andriyan Bayu Suksmono. 2024-10-13. A Quantum Approximate Optimization Method For Finding Hadamard Matrices. https://arxiv.org/abs/2408.07964

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