$f$-2$f$ self-referencing for silicon nitride photonics via a heterogeneously integrated lithium niobate layer

Weichen Fan, Bastian Ruhnke, Camiel Op de Beeck +4

Heterogeneous integration combines complementary material properties in a single photonic platform. Here, we demonstrate on-chip $f$-2$f$ self-referencing in a heterogeneously inte…