Physicists in the US have generated nuclear fusion in a simple, table-top device operating at room temperature. The device, built by Brian Naranjo, Jim Gimzewski and Seth Putterman at the University of California at Los Angeles (UCLA), causes two deuterium nuclei to collide with each other and generate alpha particles, neutrons and energy (Nature 434 1115). The device could have applications as a portable neutron generator or in the propulsion systems for miniature spacecraft, but will not be useful as an energy source because it consumes more energy than it produces.
The experimental set-up consists of a centimetre-sized cylindrical crystal of lithium tantalate (LiTaO) surrounded by deuterium gas. This material is pryoelectric, which means that positive and negative charges build up on opposite faces of the crystal when it is heated. This creates an electric field that is high enough to ionize any deuterium atoms that stray near a tiny tungsten tip attached to the positively charged surface. These deuterium ions get repelled from the surface and are accelerated by the field towards an erbium deuteride target, where the fusion reactions take place.
Fusion seen in table-top experiment
Video and Images