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arXiv · 1901.08309

Hybrid 2D/3D photonic integration for non-planar circuit topologies

Aleksandar Nesic·Matthias Blaicher·Tobias Hoose·Andreas Hofmann·Matthias Lauermann·Yasar Kutuvantavida·Martin Nöllenburg·Sebastian Randel·Wolfgang Freude·Christian Koos
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Abstract

Complex photonic integrated circuits (PIC) may have strongly non-planar topologies that require waveguide crossings (WGX) when realized in single-layer integration platforms. The number of WGX increases rapidly with the complexity of the circuit, in particular when it comes to highly interconnected optical switch topologies. Here, we present a concept for WGX-free PIC that rely on 3D-printed freeform waveguide overpasses (WOP). We experimentally demonstrate the viability of our approach using the example of a $4 \times 4$ switch-and-select (SAS) circuit realized on the silicon photonic platform. We further present a comprehensive graph-theoretical analysis of different $n \times n$ SAS circuit topologies. We find that for increasing port counts $n$ of the SAS circuit, the number of WGX increases with $n^4$, whereas the number of WOP increases only in proportion to $n^2$.

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Aleksandar Nesic, Matthias Blaicher, Tobias Hoose, Andreas Hofmann, Matthias Lauermann, Yasar Kutuvantavida, Martin Nöllenburg, Sebastian Randel, Wolfgang Freude, Christian Koos. 2019-01-24. Hybrid 2D/3D photonic integration for non-planar circuit topologies. https://doi.org/10.1364/oe.27.017402

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