Crookes Radiometer - Nanoscale Light Mill

Nanoscale Light Mill

In 2010 researchers at the University of California, Berkeley succeeded in building a nanoscale light mill that works on an entirely different principle to the Crookes radiometer. A swastika shaped gold light mill, only 100 nanometers in diameter, was built and illuminated by laser light that had been tuned to have an angular momentum. The possibility of doing this had been suggested by the Princeton physicist Richard Beth in 1936. The torque was greatly enhanced by the resonant coupling of the incident light to plasmonic waves in the gold structure.