2019-03-27, Koo, Jeongmin, Jang, Yeonsik, Martin, León, Kim, Dongku, Jeong, Hyunhak, Scheer, Elke, Kabdulov, Mikhail, Huhn, Thomas, Pauly, Fabian, Lee, Takhee

We fabricate and characterize vertical molecular junctions consisting of self-assembled monolayers (SAMs) of diarylethene (DAE) contacted by a multilayer graphene (MLG) electrode on the top and gold on the bottom. The DAE molecular junctions show two stable electrical states, a closed state (high conductance) or an open state (low conductance), which are created upon illumination with UV or visible light, respectively. For the Au-DAE-MLG junction structure, we observe that the current levels between the two conductance states are separated by two orders of magnitude. However, in a real-time measurement, we observe only unidirectional switching behavior from the open to the closed state.