Some characteristics of stimulated emission of coherent radiation from narrow-gap semiconductors

An analysis is made of those characteristics of narrow-gap crystal lasers which are associated with free-carrier absorption. It is shown that allowance for the free-carrier losses demonstrates that stimulated emission at a given wavelength is possible up to a certain temperature whose value rises on reduction in λ. The dependences of the threshold pumping intensity on the hole density at 77 °K are calculated and the optimal densities, corresponding to the threshold minimum, are found.