Prethreshold optical coupling between parts of a spatially inhomogeneous injection laser

A calculation is made of the rate of optical pumping of a weak-injection region of a two-component semiconductor laser by the radiation emitted from a strong-injection region operating in the subthreshold regime. An experimental determination is reported of the relationship between the optical and electrical coupling of the two regions. A comparison is made of the threshold characteristics of inhomogeneously excited homojunction and heterojunction lasers.