This is true enough, though remember that material properties change dramatically when you start moving through wavelengths by orders of magnitude. Silicon is t

This is true enough, though remember that material properties change dramatically when you start moving through wavelengths by orders of magnitude. Silicon is transparent in the mid-infrared, which is what makes silicon photonics possible [1] [1] https://en.wikipedia.org/wiki/Silicon_photonics https://en.wikipedia.org/wiki/Silicon_photonics