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arXiv · 2610.23499

A Fibre-Integrated SPDC Heralded Single-Photon Source Using Zn-Indiffused PPLN Ridge Waveguides at Telecom Wavelengths

Peter Iveson·Paolo L. Mennea·Goronwy Tawy·Rex H. S. Bannerman·Noe Palomar-Davidson·Greg Blanchard-Emmerson·Patrick M. Ledingham·Peter G. R. Smith·James C. Gates·Corin B. E. Gawith
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Abstract

We demonstrate a fully fibre-integrated source of broadband polarisation-entangled photon pairs at telecom wavelengths based on a commercially available Zn-indiffused MgO:PPLN ridge waveguide incorporated within a Sagnac interferometer. Operating across the full degenerate SPDC spectrum using pump-suppression filtering only, the source exhibits a measured bandwidth of approximately 67 nm. Strong non-classical correlations are observed, with an average two-photon interference visibility of 96.9 +/- 0.2 %, a fidelity to the Phi + Bell state of 78.1 %, and a CHSH Bell parameter of S = 2.501 +/- 0.005. We further explore the effect of increasing source brightness on Bell-state performance, revealing the limitations of accidental-corrected metrics in high-flux operating regimes.

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Peter Iveson, Paolo L. Mennea, Goronwy Tawy, Rex H. S. Bannerman, Noe Palomar-Davidson, Greg Blanchard-Emmerson, Patrick M. Ledingham, Peter G. R. Smith, James C. Gates, Corin B. E. Gawith. 2026-10-16. A Fibre-Integrated SPDC Heralded Single-Photon Source Using Zn-Indiffused PPLN Ridge Waveguides at Telecom Wavelengths. https://arxiv.org/abs/2610.23499

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