Quantum transport

Quantum or electron transport in a single molecule as a nano device is an importantphenomenon in molecular electronics. Recently, single-molecule devices have attractedincreasing attention due to their potential application in future atomic-scale circuits. The presenttechniques for fabricating such devices include scanning tunneling microscopy, mechanicallycontrollable break junction, conducting probe atomic force microscopy, self-assembledmonolayers, etc. Motivated by the advancement of experimental techniques, many theoreticalmethods have also been developed to better understand the mechanisms of electron transport inthe single-molecule. Among them, the functional theory (DFT) in combination with nonequilibriumGreen’s function (NEGF) is considered to be the most feasible method. On the basisof this method, various molecular devices with many interesting transport properties, such ascurrent rectification, negative differential resistance (NDR), field-effect characteristics, currentswitching, etc., have been extensively reported.