Electrically pumped InP-based microdisk lasers integrated with a nanophotonic silicon-on-insulator waveguide circuit

TLDR

An integrated silicon light source is essential for large‑scale electronic‑photonic integration. To demonstrate electrically injected continuous‑wave lasing in InP microdisk lasers coupled to sub‑micron silicon waveguides via heterogeneous integration on SOI. The device consists of a 7.5‑µm‑diameter, 1‑µm‑thick InP microdisk with a tunnel junction for efficient p‑side contact, coupled to a sub‑micron silicon wire waveguide on SOI. The laser emits at 1.6 µm with a 0.5 mA continuous‑wave threshold, 1.65 V threshold voltage, 30 µW/mA slope efficiency, and a maximum 10 µW unidirectional output.

Abstract

A compact, electrically driven light source integrated on silicon is a key component for large-scale integration of electronic and photonic integrated circuits. Here we demonstrate electrically injected continuous-wave lasing in InP-based microdisk lasers coupled to a sub-micron silicon wire waveguide, fabricated through heterogeneous integration of InP on silicon-on-insulator (SOI). The InP-based microdisk has a diameter of 7.5 mum and a thickness of 1 mum. A tunnel junction was incorporated to efficiently contact the p-side of the pn-junction. The laser emits at 1.6 mum, with a threshold current as low as 0.5 mA under continuous-wave operation at room temperature, and a threshold voltage of 1.65 V. The SOI-coupled laser slope efficiency was estimated to be 30 muW/mA, with a maximum unidirectional output power of 10 muW.