Transport phenomena in nanostructures
Magnetic multilayers are defined using molecular beam epitaxy (MBE) and structured using electron beam lithography (EBL). These devices which can have smallest structures of about 10 nm are electrically characterized. They are of central importance for the development of memory elements with a large density of structures on a chip. We investigate the switching behavior of nanoscopic magnets and the excitations, which accompany such mechanisms. Colloidal model systems help us in understanding magnetic interactions in general.
We develop techniques to electronically contact single organic molecules. Electrical current transport through single molecules has been actively investigated during the past years, because they promise new possibilities for scaling down sizes of electronic circuits. A technique for reliable fabrication of single molecule contacts, however, could not be demonstrated so far. Using EBL in combination with etching techniques we developed several such contacting techniques and use them for the electrical characterization for various molecules. Thus, we understand the electrical behavior of single molecular electronic building blocks and can use this knowledge for the development of real molecular electronic circuits.
Nanomechanical resonators can be used for example as detectors or mechanical switches. Therefore these structures offer new possibilities in generating nanoscale electrical circuits as well. The damping behavior of such structures is not well understood. The goal of our experiments is therefore to use advanced structuring methods and modern materials to investigate the damping mechanisms in nanomechanical resonators.