Waveguide-Based, high heralding efficiency biphoton source

The overall goal of this multiphase STTR program is to develop fully packaged waveguide-based biphoton sources with high brightness and ultra-high heralding efficiency. The specific goal of this phase II STTR is to refine waveguide processing and on-chip filtering demonstrated in the Phase I, towards deployable, high heralding efficiency, low SWaP systems for global quantum networking applications including two-way quantum time transfer. The key innovation is an optimized waveguide recipe combined with on-chip filtering to improve fiber coupling efficiency and reduce in-band pump fluorescence. This approach is enabled by AdvR’s demonstrated expertise in nonlinear waveguide formation combined with UIUC’s experience in field deployable systems towards quantum networking applications. The Phase I program firmly demonstrated the feasibility of this approach by fabricating modules with 85% heralding efficiency in a waveguide-based device while maintaining the high pair rates (>5MHz/mW) and indistinguishability (>90% HOM) previously established by AdvR sources. The Phase II will further optimize, integrate, and evaluate these high heralding efficiency sources towards low SWaP applications, firmly meeting the goals of STTR Topic SF22D-T005 High efficiency and high rate biphoton sources for global scale quantum networking.