N region is also observed. Testing at 80 K showed stimulated emission in the scanning mode configuration. Directly above threshold, the light increases linearly but becomes sublinear with higher currents. This is partly explained by the fact that the e-beam diameter increases with increasing current. Heating may also play a role in this sublinear behavior of the light output.
L c is the mirror loss, and G is the optical confinement factor.
The actual g m is smaller because the excitation area is not restricted by the e-beam spot. This value would be smaller if the e-beam spot diameter would be equal to the cavity length. This density is essentially greater than in GaAs and even ZnSe similar devices. This is very good for an LED because the transport of carriers to defects is limited and high efficiency is realized by localized states. Cleaved facet laser bars were prepared.