Enhanced Shot Noise in Resonant Tunneling: Theory and Experiment

We show that shot noise in a resonant-tunneling diode biased in the negative differential resistance regions of the $I-V$ characteristic is enhanced with respect to “full” shot noise. We provide experimental results showing a Fano factor of up to 6.6, and show that it is a dramatic effect caused by electron-electron interaction through the Coulomb force, enhanced by the particular shape of the density of states in the well. We also present numerical results from the proposed theory, which are in agreement with the experiment, demonstrating that the model accounts for physics relevant to the phenomenon.