In situ 3D nanoprinting of free-form coupling elements for hybrid photonic integration

Abstract

Hybrid photonic integration exploits complementary strengths of different material platforms, thereby offering superior performance and design flexibility in comparison to monolithic approaches. This applies in particular to multi-chip concepts, where components can be individually optimized and tested on separate dies before integration into more complex systems. The assembly of such systems, however, still represents a major challenge, requiring complex and expensive processes for high-precision alignment as well as careful adaptation of optical mode profiles. Here we show that these challenges can be overcome by in-situ nano-printing of freeform beam-shaping elements to facets of optical components. The approach is applicable to a wide variety of devices and assembly concepts and allows adaptation of vastly dissimilar mode profiles while considerably relaxing alignment tolerances to the extent that scalable, cost-effective passive assembly techniques can be used. We experimentally prove the viability of the concept by fabricating and testing a selection of beam-shaping elements at chip and fiber facets, achieving coupling efficiencies of up to 88 % between an InP laser and an optical fiber. We also demonstrate printed freeform mirrors for simultaneously adapting beam shape and propagation direction, and we explore multi-lens systems for beam expansion. The concept paves the way to automated fabrication of photonic multi-chip assemblies with unprecedented performance and versatility.

Fiber‐Optic SERS Probes Fabricated Using Two‐Photon Polymerization For Rapid Detection of Bacteria

“…Moreover, the 2PP technique is well suited to small‐scale substrates, which is beneficial when applied to optical fiber end‐facets 23. Thus, fabrication of sophisticated structures on optical fiber tips has been successfully demonstrated using 2PP, with examples including micro‐optics,24–27 a miniature acoustic sensor,28 a microscale force sensor,29 and a force‐sensitive micro‐grasping tool 30. In the field of SERS, 2PP has been utilized to build polymeric templates, supports, or masks for lift‐off processes of metal layers, but these were mainly based on wafer‐scale substrates 31–36.…”

Novel liquid crystal photonic devices enabled by two-photon polymerization [Invited]

“…This property differentiates TPP from the traditional photolithography and results in ultrafine 3D micro-and nano-structures. To date, TPP-based direct laser writing (DLW) has given rise to an abundance of researches on fabrication of optical components, photonic and acoustic structures, and biocompatible materials and structures [49][50][51][52].…”

3D-Printed Optics for Wafer-Scale Probing

“…The 1-dB lateral alignment tolerance amounts to  2.3 µm. The excess loss of 1.6 dB is attributed to the loss of the TIR reflection mirror, to Fresnel reflections at the lens surface and to fabrication imperfections, with significant potential for further improvement 7 . For estimation of the coupling efficiency to the TriPleX chip, we use a loop-back waveguide with 250 µm spacing between the input and output facet and measure the fiber-to-fiber loss between to be 6.2 dB, see Fig.…”