Scientists at the Georgia Institute of Technology have created nanoscale logic circuits that can be used as the basis of nanoscale robotics and processors.

The method uses Zinc oxide that has been formed as a nanowire. A voltage generated by mechanical motion induces a voltage by the piezoelectric effect which then modifies the current flowing in the wire (which is also a semiconductor). This effectively creates a tiny transistor that can be gated (open or shut, with electricity either flowing or not) by the strain applied to the nanowire.

While slower than conventional (CMOS) logic circuits, the nanoscale logic circuits are effective for low-frequency (slower) applications, including nanorobotics, transducers, micromachines, human-computer interfacing, and microfluidics.

More info: W. Z. Wu, Y. G. Wei, and Z. L. Wang, “Strain-Gated Piezotronic Logic Nanodevices”, Advanced Materials 2010, DOI: 10.1002/adma.201001925