A NEW 'TWIST' ON NANOSTRUCTURES

摘要

Zinc-oxide nanostructures resembling a DNA helix could let engineers build nanoscale sensors, transducers, resonators, and other devices that rely on electromechanical coupling, say developers at the Georgia Institute of Technology. These so-called nanohelices have both piezoelectric and semiconducting properties. They get their shape from twisting forces caused by a small mismatch between alternating single-crystal "stripes" just 3.5 nm wide that are offset by about 5°. The nanohelices are roughly 100 μm long, about 300 to 700 nm in diameter, and from 100 to 500 nm wide. They come in both right and left-handed versions, with production split nearly 50-50 between the two directions.