Conductance Hysteresis and Switching in a Single-Molecule Junction

Voltage-controlled conductance hysteresis and stepwise switching in a reversible manner were observed in a single-molecule double-barrier junction defined by a scanning tunneling microscope (STM) at ∼10 K. In situ visualization and characterization of the junction using the STM revealed that the charge bistability of a single molecule on a polar alumina film is responsible for the conductance hysteresis and switching. It was also found that the relative stability between different charge states depends on the multiple adsorption configurations of molecules on the surface.