In a typical optical link, data is first transferred from the electrical to the optical domain using an or a directly modulated laser. An electro-optic modulator can vary the intensity and/or the phase of the optical carrier. In silicon photonics, a common technique to achieve modulation is to vary the density of free charge carriers. Variations of electron and hole densities change the real and the imaginary part of the refractive index of silicon as described by the empirical equations of Soref and B.
[pdf] Bogdan Sirbu: One example I can think of is the H2020 L3MATRIXproject. On this project, we developed a 2D matrix of 64 different transceiver and receiver cells, achieving high radix and getting an extend.
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