It won't power the starship Enterprise, but an experimental "dilithium crystal" pyroelectric technology is said to enable compact nuclear fusion. Engineers at Rensselaer Polytechnic Institute (Troy, N.Y.) said they have opposed two oppositely charged centimeter-sized lithium tantalate crystals to create a fusion device that can operate off a battery at room temperature. "In a [conventional] fusion device de- signed to produce energy, the release of high-energy ions further heats the plasma, thereby sustaining the reaction. We get the same amount of energy out of the fusion reaction, but we cannot use it to sustain the reaction," said the technique's inventor, associate professor Yaron Danon. "Instead, we plan to use the energy emitted to create a portable neutron source that has applications in non- destructive testing or, possibly, explosive-mine detection," he said. Indeed, Danon predicts that different application areas will benefit from the four types of high-energy particles that a pyroelectric crystal accelerator can emit: high-energy electrons, ions, neutrons and X-rays. The electrons that pyroelectric crystals produce could be used for therapeutic purposes, such as cancer treatments, he said. With some improvements, the high-energy emissions might be used to inspect cargo or scan luggage. Danon performed his research for the Department of Energy with Jeffrey Geuther and Frank Saglime, doctoral candidates in nuclear engineering.