I forgot to  mention one very important aspect of the POET platform which seemed to be highlighted a number of  times by the new marketing guy. Known good die. Because the active devices are produced separately and contained on their own die they are tested and known to be of high quality before they are assembled. Not the case for example where germanium implants are used in the silicon for detection. A fail of any one of these detector implants especially where a large number are used for 400G and greater results in the loss of the whole package. Thus yield in terms of final assembly is very high when compared to companies like Rockley who will typically utilize as much monolithic capability afforded by the silicon wafer as possible.