Electron Transport Through Thiolized Gold Nanoparticles in Single-Electron Transistor

Abstract

We propose an analytical parametric model for defining energy spectra of nanoparticles with a number of atoms of up to 3,300. This allows us to perform Monte-Carlo simulations for single-electron transistor (SET) based on gold nanoparticles with a size of up to 5.2 nm at temperatures from 0.1 to 300 K. At the first step, energy spectra were calculated for isomers of gold nanoparticles, consisting of up to 33 gold atoms using methods of quantum mechanics: density functional theory (DFT) with LANL2DZ basis set for “geometry” optimization; unrestricted Hartree–Fock method (UHF)x with SBKJC basis set to evaluate energy parameters of nanoobjects, which include gold atoms with many electrons. It was found that the general structure of the energy spectra changes unsignificantly if the number of atoms is greater than 27. Moreover, the size of the energy gap and the position of energy levels in it are linear functions of one parameter—the total electric charge of the nanoparticle. These features of energy spectra allowed us to perform calculations of the transport characteristics for a real SET using gold nanoparticle as a central conducting island.