NSF Unit Consideration: CPA - Foundations of Computing Processes and Artifacts The proposed work is on constructing reconfigurable logic and devising defect detection, diagnosis and tolerance techniques for Quantum-dot Cellular Automata (QCA) based nano-scale devices. QCA- based devices differ fundamentally from traditional CMOS ones. They have the potential to alleviate challenges from interconnects and power consumption as CMOS device sizes continue to shrink. Basic QCA constructs have been experimentally demonstrated with both semiconductor quantum dots and nano-magnets. Implementing QCA devices with molecular charge containers has also shown great promise. Though being a promising computing paradigm, QCA faces a same challenge as all other nano-scale devices. That is, defect rates are expected to be high. Reconfigurable logic and defect tolerance design are considered to be two powerful means to circumvent the effects of high defect rates. This project will significantly extend the state-of-the-art in constructing reconfigurable logic under the QCA model.
Successful completion of the project will lead to both novel reconfigurable logic constructs and new defect detection and diagnosis schemes. The proposed work will help predict whether it is practical to fabricate large scale QCA-based reconfigurable circuits, and whether such circuits can become a strong contender as a post-CMOS computing alternative. The proposed work will have a significant impact not only within the design community but also in the physical science community. It will contribute new knowledge in designing reconfigurable logic and circuits in the context of charge-coupled computing models. It will also play an important role in providing valuable feedback to physical scientists working on exploring various technologies for implementing QCA devices. As an integral part of the proposed work, a new course module on QCA- based computing will be developed, which emphasizes the interdisciplinary nature in this exciting research area. A systematic endeavor will be made in recruiting undergraduate students, especially from the under-represented groups, to participate in the project.