European Conference on Antennas and Propagation

Topological On-Chip Quantum Photonics for Nonlinear Biphoton Entanglement

Hesam Zaravashan, Maryam Khodadadi, Ali Ali, Gabriele Gradoni, Mohsen Khalily

Published Apr 1, 2026• 0 citations

Abstract

Integrated quantum photonics promises scalable quantum technologies but remains limited by fabrication-induced disorder, phase instability, and loss, which degrade interference and entanglement. In this paper, a fully topological approach to both linear routing and nonlinear biphoton generation is demonstrated on the same chip. A valley-Hall lattice is engineered to create a dispersion-stable edge mode that supports spontaneous four-wave mixing with efficient phase matching. The generated signal-idler photon pairs are routed by a topological power splitter that maintains a 50:50 ratio and preserves relative phase, even through a sharp 60° bend. Strong suppression of backscattering and minimal dispersion enable high-visibility twophoton interference without active recalibration. This unified platform simultaneously provides robust guiding, coherent splitting, and high-fidelity entanglement generation, overcoming key limitations of conventional integrated photonics. These results establish topological photonic structures as a practical route toward fabrication-tolerant, phase-stable, and scalable quantum light sources and circuits for next-generation quantum communication, computation, and sensing.

DOI: 10.23919/eucap68105.2026.11612727

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