Combinational logic based on chemically designed cluster-ligand systems with electrical addressing of quantum states

• Applicants: Dr.-Ing. Silvia Karthäuser; Professor Dr. Ulrich Simon
• Subject Area: Solid State and Surface Chemistry, Material Synthesis
• Term: from 2007 to 2010
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 27685451

We propose to develop prototypical combinational logic machines using electronic quantum states of self-assembled exchange-coupled few nanodot arrays. Small core Au clusters will be functionalized with suitable ligands. Nanoelectrodes will electrically address the states of the array formed by assembling a few dots. Theory will determine the possible states taking into account the Coulomb blocking of charge transfer, the different aspects of disorder and the role of the ligands. The design seeks to go beyond switching arrays and to integrate directly Boolean operations for the implementation of logic gates, such as half- and full-adders, on a few-dot array. We aim to fabricate a demonstrator of such logic gates working at room temperature, to perform electron transport studies, to verify the computational results, and to use theory to further optimize the performance. For this, functional Au clusters with well-defined core-sizes of less than 2 nm will be synthesized. These will be arranged by directed self-assembly processes between lithographically predefined and, in a second stage, tailored nanoelectrodes in order to fabricate multiple terminal devices. Using this approach nanometer scale integration of devices for information processing at the hardware level will be demonstrated. A longer-term goal is to extend the capability of the design to that of a finite state logic machine.

• DFG Programme: Research Grants
• International Connection: Israel