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] A semiconductor laser is a type of laser where the active gain medium is a semiconductor. Their theoretical description is important not only from a. A laser diode (LD, also injection laser diode or ILD or semiconductor laser or diode laser) is a semiconductor device similar to a light-emitting diode in which a diode pumped directly with electrical current can create lasing conditions at the diode's junction. Hall and, largely because they're so compact and inexpensive, are now the most widespread lasers in the world.
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