The Development of Quantum-Dot Cellular Automata - Field-Coupled Nanocomputing: Paradigms, Progress, and Perspectives - page 14

from both industrial researchers [ 101 , 102 ] and philosophers of science [ 103 , 104 ].
The low power dissipation in QCA is an example of LP in action [ 105 ]. We have
recently demonstrated experimentally that a binary switch can be operated with dis-
sipation of 0.01 k B T, in agreement with LP [ 106 - 108 ].

5 Future Prospects

QCA research activity continues on several fronts. Molecular QCA will require
improved understanding of the chemistry of mixed-valence molecules. This includes
exploring linker and dot moieties, the role of ligand relaxation in charge transfer,
surface attachment and molecular-scale patterning. Significant progress in nanomag-
netic implementations is reported by several other contributors in this collection.
Metal-dot QCA deserves more exploration, even though it requires cryogenic oper-
ation. New fabrication methods may raise the operating temperature considerably.
Exploration of circuits and computational architectures is crucial for fully exploiting
the potential of locally interconnected nanodevices.

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