Computational Investigation of DNA Detection Using Single-Electron Transistor-Based Nanopore

We propose a single-electron transistor (SET)-based nanopore sensor for DNA sequencing, which consists of source, drain, and gate electrodes, as well as a nanopore where the DNA molecule is pulled through. For nanopore sensors based on transverse electronic transport, generally, the tunneling current is relatively small due to the weak coupling between the molecule and electrodes. We take full advantage of this feature by introducing SET to make the device operate in Coulomb-blockade regime. Through first-principles simulations, the charge stability diagrams of the nucleobases within the SET-nanopore environment are demonstrated to be distinctive for each molecule and, more importantly, independent of the nucleobase orientation, which can be served as electronic fingerprint for detection. We show that identifying the nucleobases can be achieved only though several specific regions or points in the diagram.