Facet-attached micro-lenses and beam-shaping elements

Hybrid photonic integration combines complementary advantages of different material platforms, offering superior performance and flexibility compared with monolithic approaches. This applies in particular to multi-chip concepts, where components can be individually optimized and tested.

Up to now the assembly of such systems, however, requires expensive high-precision alignment and adaptation of optical mode profiles.

We have shown that these challenges can be overcome by in situ printing of facet-attached beam-shaping elements. Our approach allows precise adaptation of vastly dissimilar mode profiles and permits alignment tolerances compatible with cost-efficient passive assembly techniques.

P.-I. Dietrich et al., Nature Photonics volume 12, pages 241–247 (2018)

We demonstrated a selection of beam-shaping elements at chip and fiber facets, achieving coupling efficiencies of up to 88% between edge-emitting lasers and single-mode fibers. We also realized printed free-form mirrors that simultaneously adapt beam shape and propagation direction, and we explored multi-lens systems for beam expansion.

The concept paves the way to automated assembly of photonic multi-chip systems with unprecedented performance and versatility.