Tunable Quantum Resonance in Self Assembled Nanoelectronics

Continuous miniturization of small, functional electronic devices like they can be found on computer-chips requires novel technologies. Promising ideas include the use of single molecules as the smallest logical unit of a device. Clearly, such molecular devices cannot be built freestanding, but have to be arranged on some surface in order to establish a contact to the macroscopic world. A very convenient way to attach special molecules onto a surface in a highly orderd manner is the fabrication of a "Self Assembled Monolayer". Many identical molecules are chemically bound to he surface in a densly packed, periodic pattern. Thus, a special functional surface layer has been created that is only as thick as the molecules are long. These molecules can then be wired up to work as a logical eletronic device. Using modern laboratory equipment, molecule size objects on surfaces can be structured, visualized, and analyzed. However, on the considered length scale, most measurable effects are of quantum mechanical nature. Hence, the interpretation of experimental data and the underlying physics is not always easy. The aim of this project is to develop a consistent methodology that will allow to perform quantum mechanical calculations on molecule/surface systems. These calculations should be conducted on systems that correspond to the experimental situation, which has not been possible so far due to the sheer size of the systems. With the aid of supercomputers and special computational techniques, experimental data could be reliably reproduced, explained and predicted. The properties of self assembled monolayer based molecular devices will be studied on a microscopic level in order to push ahead this novel technology.