Stimulated emission divided by the input intensity: Substituting this definition into the prior equation, we find the general gain equation: In the special case where the input signal is small compared to the saturation intensity, in other words, then the general gain equation gives the small signal gain as or which is identical to the small signal gain equation (see above). For large input signals, where the gain approaches unity and the general gain equation approaches a linear asymptote: .3 Laser Fundamentals, William T. Silfvast Stimulated emission Stimulated emission is the process by which an incoming photon of a specific frequency can
Sound amplification by stimulated emission of radiation electrons become localized in the quantum wells and vertical electron transport takes place via hopping between neighboring quantum wells, which may be phonon assisted. As it had been shown previously, under these conditions stimulated phonon emission can become the dominant phonon-assisted hoping process for phonons of an energy value close to the Stark splitting. Thus, coherent phonon amplification is theoretically possible in this type of system. Together with the increase in amplitude, the spectrum of the bias-induced oscillations is narrower than the spectrum of the coherent phonons at zero bias. This shows that coherent amplification of phonons due to stimulated