I'm sorry, this is not an easy read, well it could be for the techies...

However, after reading it, it made me feel comfortable about what is continuously being said on this forum and by POET. This is why I'm sharing it.

Abstract below:

6. Device integration

While the development of single quantum photonic devices is very intense across many material platforms, the efficient integration of these devices on the same chip is required to unlock the power of integrated quantum photonics.

Therefore, we propose a qualitative comparison of different elementary platforms based on the degree of integration reported in literature. Table 1 shows examples of integrated chips where we have attempted to capture at the same time a spectrum of different devices and the highest degree of integration achieved to date.

Each platform is represented by a different color and each line in the table corresponds to the devices demonstrated within a single paper. The filled cells mark the availability of the corresponding device and the darker shaded cells indicate the devices that are particularly suitable for quantum applications.

Such comparison is necessarily subjective and does not include all the platforms mentioned in this review.

Si and LiNbO3 display a particularly high degree of integration, given their long history of development as photonic materials. Based on these platforms, on-chip systems consisting of four or more different categories of devices have been demonstrated.

We remark, however, that no system up to date demonstrates on-chip integration of all components.

Moreover, amongst the elementary platforms, perhaps, only the III-V materials currently offer the entire range of required on-chip devices ranging from a pump laser to single-photon detectors. They therefore appear the most likely to achieve full integration within the next few years.

Please, feel free to read more at: https://arxiv.org/ftp/arxiv/papers/1610/1610.00729.pdf