World’s smallest electric rotor made

July 24, 2003 | Source: Nature Science Update

Scientists have built an electric rotor with a gold blade 300 nanometers long. This sits atop an axle made from a multiwalled carbon nanotube; gold electrodes at either end of the axle lash the device to a silicon chip.

Applying a voltage between the nanotube and one of three more electrodes around it rotates the blade. The nanotube rotor can operate at great speed, over a wide range of temperature and chemical conditions –even in a vacuum.

This lends it to a wide range of applications, such as a mirror to direct and switch light signals rapidly and detecting the presence of certain chemicals attached to its blade by monitoring its resonant rotational speed.