NEGATIVE DIFFERENTIAL RESISTANCE DUE TO RESONANT INTERBAND TUNNELING OF HOLES

The current-voltage (I-V) behavior of a GaSb(p)/AlSb/InAs/AlSb/GaSb(p) resonant interband tunneling (RIT) heterostructure is analyzed experimentally and theoretically. The structure has been successfully grown on a (100)-oriented GaAs substrate by molecular-beam epitaxy, demonstrating that more exotic lattice-matched substrates (such as InAs or GaSb) are not required for RIT devices. Theoretical simulations of I-V behavior are developed, employing a two-band tight-binding model. Experimental I-V curves show pronounced negative differential resistance, with a peak-to-valley current ratio of 8.3 at 300 K. Good agreement is observed between measured and calculated peak current densities, consistent with light-hole tunneling through the confined InAs conduction-band state.