Nanosystems

The Technology Roadmap for Productive Nanosystems defines "productive nanosystems" as functional nanometer-scale systems that make atomically-specified structures and devices under programmatic control, i.e. they perform manufacturing to atomic precision. Such devices are presently only hypothetical.

Present-day technologies are limited in various ways. Large atomically precise structures exist, in the form of crystals. Complex 3D structures exist in the form of polymers such as DNA and proteins. It is also possible to build very small atomically precise structures using scanning probe microscopy to manipulate individual atoms or small groups of atoms. But it is not yet possible to combine components in a systematic way to build larger, more complex systems.

Principles of physics and examples from nature both suggest that it will be possible to extend atomically precise fabrication to more complex products of larger size, involving a wider range of materials. An example of progress in this direction would be Christian Schafmeister's work on bis-peptides.

Mihail Roco, one of the architects of the USA's National Nanotechnology Initiative, has proposed four states of nanotechnology that seem to parallel the technical progress of the Industrial Revolution, of which productive nanosystems is the most advanced.

1. Passive nanostructures - nanoparticles and nanotubes that provide added strength, electrical and thermal conductivity, toughness, hydrophilic/phobic and/or other properties that emerge from their nanoscale structure.

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