Hybrid Silicon Microlasers with Gain Patches of Unlimited Designs

Integrating the smallest possible lasers into silicon photonics has long been an objective of photonic integrated circuits. However, efficient combining of small lasers to silicon photonics has been a major challenge because of the need to overcome meticulous laser designs and flawless alignments. In this paper, we propose and demonstrate a new concept of hybrid silicon microlasers that are automatically integrated into silicon photonics by simply placing III–V gain patches with no restrictions of design and alignment onto silicon microcavities. Our simulations suggest that a thin (∼180 nm) InGaAsP slab patch provides sufficient optical gain to operate the laser with little effect on the original silicon microcavity mode. We printed 180 nm thick InGaAsP patches with various designs onto silicon microring resonators using transfer-printing techniques and experimentally observed that they were all operated as lasers with high alignment tolerances.