6 Experimental studies of quantum - dot cellular automata devices

The ultimate nanodevice is the “quantum dot” since that implies confinement in all three dimensions. Heretofore, no Boolean logic scheme has been proposed that is based on coupling of quantum dots. A team of researchers at the University of Notre Dame has devised and demonstrated the fundamental properties of a computing paradigm called “Quantum-dot Cellular Automata (QCA)” QCA could be accomplished in several different material systems, including semiconductor dots, metal dots, nanomagnets, or molecules. In this paper we review a series of experiments demonstrating the fundamental properties of QCA devices implemented in metal dots. Devices include basic cell, majority and other logic gates, latches, and shift registers. The chapter concludes with a discussion of sources of errors in QCA logic circuits. Correspondence/Reprint request: Dr. Alexei O. Orlov, Dept. of Electrical Engineering, University of Notre Dame, Notre Dame IN 46556. E-mail: [email protected] Alexei O. Orlov et al. 2