Enabling VCSEL-on-silicon nitride photonic integrated circuits with micro-transfer-printing

Jeroen Goyvaerts,Alexander Grabowski,Johan Gustavsson,Sulakshna Kumari,Günther Roelkens,Andim Stassen,Roel Baets,Anders Larsson

doi:10.1364/optica.441636

Abstract

New wavelength domains have become accessible for photonic integrated circuits (PICs) with the development of silicon nitride PICs. In particular, the visible and near-infrared wavelength range is of interest for a range of sensing and communication applications. The integration of energy-efficient III-V lasers, such as vertical-cavity surface-emitting lasers (VCSELs), is important for expanding the application portfolio of such PICs. However, most of the demonstrated integration approaches are not easily scalable towards low-cost and large-volume production. In this work, we demonstrate the micro-transfer-printing of bottom-emitting VCSELs on silicon nitride PICs as a path to achieve this. The demonstrated 850 nm lasers show waveguide-coupled powers exceeding 100 µW, with sub-mA lasing thresholds and mW-level power consumption. A single-mode laser with a side-mode suppression ratio over 45 dB and a tuning range of 5 nm is demonstrated. Combining micro-transfer-printing integration with the extended-cavity VCSEL design developed in this work provides the silicon nitride PIC industry with a great tool to integrate energy-efficient VCSELs onto silicon nitride PICs.

Highlights

Over the past two decades, the field of silicon photonics has steadily been gaining momentum
The vertical-cavity surface-emitting lasers (VCSELs)-component parameters are extracted from the top-surface-emitting VCSELs on the source substrate and the bottom-surface-emitting VCSELs that are printed on the transparent sapphire substrate
We have demonstrated the integration of a vertical cavity laser on a SiNx photonic integrated circuits (PICs) using a bidirectional diffraction grating coupler

Summary

Introduction

Over the past two decades, the field of silicon photonics has steadily been gaining momentum. The demonstrations include chip-level integration of edge-coupled gain chips and lasers [1] and wafer-level integration via bonding [2], flip-chipping [3], micro-optical-benches [4] and micro-transfer-printing [5]. Low-loss propagation and new wavelength bands became accessible for PICs. there have been similar efforts in chip-level integration [6], and wafer-level integration of gain chips and laser diodes [7, 8]. There have been similar efforts in chip-level integration [6], and wafer-level integration of gain chips and laser diodes [7, 8] All these lasers share planar cavities with planar emission and have cavity lengths ranging from a few hundred micron to a few millimeter. Associated with the larger cavity length are the relatively high threshold currents, in the range of 10 to 100 mA

Methods

Results

Conclusion