In this article, there were typographical errors. In third paragraph in Introduction section, “have thus far been demonstrated” should be deleted. The correct sentence is as follows. Thanks to the high absorption coefficients and pseudo-direct band-gap properties of Ge near the C-band communication wavelengths, active photonic devices (light sources and photodetectors) in Si PICs are enabled [2, 3] with small form factors on 2-D silicon-on-insulator (SOI) platforms. Moreover, at the end of third paragraph in “4.1 SiN‑embedded Ge‑QD microdisk light emitters”, unnecessary "Ge QD SiN silicon oxide air" has been remained. That should be deleted. The original article has been corrected.