Resonant Tunneling Transport in a GaN/AlN Multiple-Quantum-Well Structure

In this work, we have investigated the vertical electron transport through a seven-period GaN/AlN multiple-quantum-well structure. The devices show asymmetric current-voltage characteristics displaying negative differential resistance at room temperature. These features persist for multiple scans and are reproducible for both upward and downward sweeping voltages. We interpret the negative differential resistance as a consequence of the resonant tunneling between the fundamental and excited states of adjacent quantum wells. The experimental results are in good agreement with the predictions of an electron transport simulation. (c) 2012 The Japan Society of Applied Physics