Quench of hot-electron real space transfer by electronic screening

The authors report a study of the hot-electron real space transfer (RST) between two InGaAs layers separated by a 200-nm InAlAs barrier. The electron heating is generated by an electric field applied parallel to one of the layers, which represents a two-dimensional hot-electron emitter. Strong suppression of the RST by an increased concentration n_s of the emitter electrons was observed. With increasing n_s, the critical heating voltage, required to initiate the RST, increases. At a fixed heating voltage, a sudden quench of the RST is observed as n_s increases. Both phenomena are explained by an electronic screening effect which smooths out the nonuniformity of the electric field in the emitter channel