A Current-Driven Single-Atom Memory
Dr. Christian Schirm (Universität Konstanz)

This talk will show an experimental realization of a functional electrical device on the atomic scale. The device is a reversible atomic switch made of aluminum, operated electrically by two electrodes. The experimental setup will be presented, the verification of the results and the comparison to theoretical calculations. One major technique for the electrical characterization of conductive nano systems is the analysis of the so called Multiple Andreev-Reflections (MAR). The MAR characteristics allow us to identify single quantum states of the electrical current. The spectra of these so called conduction channels are used to identify the different switching states of the nano device. They also act as a link between the experiment and theoretical simulations. Each channel can contribute to the total conductivity with a maximum conductance of G0, the so called “quantum of conductance”. The meaning of the conduction quantization will be discussed. Finally, the atomic switch will be considered for a potential application in non-versatile memory devices.