Silicon and germanium are transparent in a broad range of the long-wave IR and therefore can be used as photonics platforms in this wavelength region. Furthermore, the free carrier plasma dispersion effect should be stronger, two photon absorption is reduced, and more robust optical bers are now available at longer wavelengths. In addition, the dimensional tolerances are more relaxed than in the near-IR. Moreover, III-V sources and detectors could be bonded on the silicon wafer, similar to approaches already demonstrated in the near-IR. Finally, silicon photonics, or group IV photonics, long wavelength platform is potentially low-cost and offers a possibility of photonicelectronic integration.