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arXiv · 2306.06539

A Universal Quantum Algorithm for Weighted Maximum Cut and Ising Problems

Natacha Kuete Meli·Florian Mannel·Jan Lellmann
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Abstract

We propose a hybrid quantum-classical algorithm to compute approximate solutions of binary combinatorial problems. We employ a shallow-depth quantum circuit to implement a unitary and Hermitian operator that block-encodes the weighted maximum cut or the Ising Hamiltonian. Measuring the expectation of this operator on a variational quantum state yields the variational energy of the quantum system. The system is enforced to evolve towards the ground state of the problem Hamiltonian by optimizing a set of angles using normalized gradient descent. Experimentally, our algorithm outperforms the state-of-the-art quantum approximate optimization algorithm on random fully connected graphs and challenges D-Wave quantum annealers by producing good approximate solutions. Source code and data files are publicly available.

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Natacha Kuete Meli, Florian Mannel, Jan Lellmann. 2023-06-10. A Universal Quantum Algorithm for Weighted Maximum Cut and Ising Problems. https://arxiv.org/abs/2306.06539

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