Four-qubit variational algorithms in silicon photonics with integrated entangled photon sources

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 circu...

Full description

Saved in:
Bibliographic Details
Main Authors: Alessio Baldazzi, Matteo Sanna, Massimo Borghi, Stefano Azzini, Lorenzo Pavesi
Format: Article
Language:English
Published: Nature Portfolio 2025-07-01
Series:npj Quantum Information
Online Access:https://doi.org/10.1038/s41534-025-01061-6
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary: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 semiprime 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.
ISSN:2056-6387