Negative differential resistance through real‐space electron transfer

A new mechanism is proposed to obtain negative differential resistance in layered heterostructures for conduction parallel to the interface. The mechanism is based on hot‐electron thermionic emission from high‐mobility GaAs into low‐mobility AlxGa1−xAs. Preliminary calculations indicate that high peak‐to‐valley ratios can be achieved. The transfer speed is estimated to be of the order of 10−11 s. We further show that the concept of hot‐electron thermionic emission can be applicable to a variety of devices.