scientists at the Bangalore-based Indian Institute of Science (iisc) have found that a jet of gas can generate current if passed over materials like semiconductors. Physicists Ajay Sood and Shankar Ghosh made the discovery by using just a bottle of compressed gas and equipment made at very low cost. The findings, appearing in the Physical Review Letters (Vol 93, No 8, August 20, 2004), have drawn considerable peer attention.

The scientists passed the compressed gases (oxygen, nitrogen and argon) at velocities ranging from a few kilometres per hour to 350 kilometres per hour over various materials