Fano resonances in current-voltage characteristics of nanowires with embedded quantum dots

The electron transport has been studied in a nanowire with a quantum dot (QD) embedded between two barriers, i.e., in a quasi-one-dimensional resonant tunneling diode (RTD). The current-voltage characteristics of the RTD have been calculated taking into account the smoothness of the QD/barrier interfaces and the presence of spacers separating the barriers from the contacts. We have found that the application of narrow spacers essentially modifies the shape of the resonant current peak. The resonant peak possesses the symmetric shape for wide spacers and becomes asymmetric acquiring the Fano resonance shape for sufficiently narrow spacers. The results of calculations agree well with the experimental data for the resonance tunneling in the InP/InAs/InP nanowire.