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arXiv · 2505.14269

Rubidium-Doped KTiOPO$_4$ Waveguides as a Dual-Type Photon Pair Source

Patrick Hendra·Josué R. León-Torres·Valerio Flavio Gili·Markus Gräfe
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Abstract

We investigate the dual generation of type-0 and type-II spontaneous parametric down conversions (SPDCs) within a single periodically poled rubidium-doped KTiOPO$_4$ (PPRKTP) waveguide. By coupling a 45 degree linearly polarized pump laser into the waveguide, both SPDC processes are concurrently excited: the type-0 SPDC process is facilitated via third-order quasi-phase matching (QPM) utilizing the nonlinear coefficient $d_{33}$ , while the type-II SPDC process employs first-order QPM with the nonlinear coefficient $d_{24}$. This dual-SPDC scheme holds potential for applications in quantum communication protocols targeting the telecommunication wavelength.

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Patrick Hendra, Josué R. León-Torres, Valerio Flavio Gili, Markus Gräfe. 2025-05-20. Rubidium-Doped KTiOPO$_4$ Waveguides as a Dual-Type Photon Pair Source. https://doi.org/10.1364/josab.567775

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