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arXiv · 2501.01301

Four-Qubit Variational Algorithms in Silicon Photonics with Integrated Entangled Photon Sources

Alessio Baldazzi·Matteo Sanna·Massimo Borghi·Stefano Azzini·Lorenzo Pavesi
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Abstract

Variational quantum algorithms are hybrid quantum-classical approaches extensively studied for their potential to leverage near-term quantum hardware for computational advantages. In this work, we successfully execute two variational quantum algorithms on a silicon photonic integrated circuit at room temperature: a variational quantum eigensolver for the Hydrogen molecule and a variational quantum factorization for semi-prime numbers. In our reconfigurable silicon photonic circuit, four identical spontaneous-four-wave-mixing-based integrated photon pair sources are used to prepare two path-entangled ququarts, whose correlation gives rise to the resource for generic trial states' preparation. This marks a first demonstration of variational quantum algorithms on a photonic quantum simulator with integrated photon pair sources.

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Alessio Baldazzi, Matteo Sanna, Massimo Borghi, Stefano Azzini, Lorenzo Pavesi. 2025-01-02. Four-Qubit Variational Algorithms in Silicon Photonics with Integrated Entangled Photon Sources. https://arxiv.org/abs/2501.01301

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