Experts are still uncertain about the best way to optelectronic integration, according to statements from the OFC. It seems silicon photonics (SiP) and indium phosphide (InP) are the leading candidates, but this isn't settled at all yet.
What's more, "integration" is not a precisely defined term. It does not necessarily mean monolithic integration, but could as well pertain to better packaging or other process improvements. Monolithic integration is something POET's gallium arsenide (GaAs) process provides – which isn't really on the radar yet.
Read more in this EE Times article:
OFC Debates Road to Photonic ICs