High transconductance and large peak-to-valley ratio of negative differential conductance in three-terminal InGaAs/InAlAs real-space transfer devices

Three-terminal real-space transfer devices with improved room-temperature characteristics have been implemented in InGaAs/InAlAs/InGaAs heterostructures lattice matched to InP. The devices exhibit extremely sharp charge injection, characterized by a transconductance exceeding 23 S/mm and a negative differential conductance with a peak-to-peak ratio of over 7000. Our experiments suggest that both of these characteristics are limited only by the dielectric strength of the InAlAs barrier layer.