Evidence for attainability of negative differential conductance in tunnel Schottky structures with two-dimensional channels

Experimental data, which demonstrate conductance decrease in the tunnel Al/GaAs Schottky structure with delta-n-doped two-dimensional channel, are presented. The conductance decreases due to the increase in the tunnel-barrier height with bias and the corresponding drop in the barrier tunnel transparency. Theoretical calculations show that the mechanism should lead to the negative value of the differential conductance if the separation between the subbands in the two-dimensional channel is sufficiently large. On the basis of calculations, an (ErAs)Al/InAlGaAs/InAlAs/InP heterostructure is suggested, where the negative differential conductance should be reached. (C) 2007 American Institute of Physics.