We derive an analytical expression for the intrinsic gain suppression
factor based on carrier heating. The theory shows good agreement with
the published experimental value of epsilon = + 1.5 x 10(-17) cm3 for
in-plane lasers. For the first time, we predict and experimentally obs
erve a negative gain suppression factor for particular laser designs.
A negative gain suppression factor can lead to the elimination of damp
ing in semiconductor lasers. Using vertical-cavity surface-emitting la
sers, we observe a negative gain suppression factor of -2.2 x 10(-17)
cm3.