FIRST-PRINCIPLES STUDY ON PHOTOSWITCHING BEHAVIOR IN SINGLE MOLECULE JUNCTION.

We carry out first-principles calculations based on density functional theory and non-equilibrium Green's function to investigate the electronic transport properties of a diarylethene-based molecule sandwiched between two Au electrodes. This molecular switch can be reversed between open and close forms by using light stimulation. We analyze the switch behavior of these two forms through the current-voltage curves, transmission spectra and molecular projected self-consistent Hamiltonian. It has been found that the current of the close form is significantly larger than the open form, and there is a large and stable switch ratio in a wide bias window. This result indicates that this molecule can become one of the good candidates for optical molecular switch in the future. [ABSTRACT FROM AUTHOR]