"You just heat the crystal from room temperature to about 130 degrees," team leader Yaron Danon told SpaceDaily.com. "Then you can use it while it's heating or while it's cooling. We're doing it while it's cooling. We're letting it cool back to room temperature, and while it's doing that it's accelerating ions, so it's like a particle accelerator that's very simple."

Danon said the device is so small and efficient it requires only a 6-volt battery, but because it also emits neutrons - which in sufficient numbers can be harmful or deadly - operating it requires caution.

"Currently we are emitting two to the fourth or two to the fifth (neutrons during) a heating cycle, which lasts for about 200 seconds," he explained. "We're several meters away, so the dose rate at that distance is really low. If it gets to be the same amount (of neutrons emitted) for a shorter time, then we have to be very careful."

The device uses a pair of the crystals encased in a chamber of deuterium gas. The crystals create a very strong electric field when they are heated or cooled, and the field produces deuterium ions by ripping electrons from the gas and accelerating them toward a deuterium target on one of the crystals. When a deuterium ion smashes into the target, a neutron is emitted, the telltale sign that nuclear fusion has occurred.

"We published several papers explaining how these crystals produce X-rays and electron beams, and they're very efficient in doing this," Danon said. "So using low-energy X-rays or low-energy electron beams - by which I mean similar to the energies that are used currently in medical imaging rather than treatment - we can produce a really high dose of electrons that can penetrate a very thin layer of the skin. If such a device can produce high enough dose, then we can possibly use it for cancer treatment - and we're not far from this goal."

He said eventually the device could lead to portable, battery-operated neutron generators for a variety of applications, from non-destructive testing to detecting explosives and scanning luggage at airports. "We're trying to figure out better ways to produce more neutrons, and to see how we can use our device for X-rays for imaging applications. We are also trying to develop a higher-dose device for medical applications," he added. "All these applications are using the polarization effect that occurs when heating or cooling pyroelectric crystals."

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