High-speed tunneling-barrier GaAs light emitters

High-speed GaAs light-emitting diodes are described that contain a single-AlAs tunneling barrier for localization of the carriers. These devices are identical to double-barrier resonant tunneling light emitters in speed and efficiency, but are not dependent on resonant tunneling of charge carriers. An external quantum efficiency of 0.18% and a 3-dB modulation bandwidth of 1.3 GHz are reported. These devices are less affected by nonradiative recombination compared to the conventional heavy-doping approach, in which a high-modulation bandwidth is obtained at the expense of a more than proportional reduction in quantum efficiency.