Small device could solve big security problems

Researchers at the University of Nebraska-Lincoln have developed a fingertip-sized neutron detector that could be used to locate hidden nuclear materials or monitor stored nuclear weapons.

A highly sensitive, fingertip-sized neutron detection device developed by University of Nebraska-Lincoln researchers could be used for locating hidden nuclear materials or monitoring nuclear weapons storage.

The detector, built around a boron-carbide semiconductor diode can detect neutrons emitted by the materials that fuel nuclear weapons.

‘This is a leapfrog technology in neutron detection,’ said Peter Dowben, UNL physicist who was the first to fabricate a boron carbide semiconductor. Using Dowben’s boron carbide semiconductors, the research team built a detector that is said to be much more efficient, lighter, and tougher than existing detectors.

‘This device is very small, it can be powered with small batteries or even solar cells, and it can withstand corrosion and extremely high temperatures,’ said team member, Brian Robertson.

Five patents are held by UNL or are pending on the processes for producing the semiconductors and on the device itself. The team is continuing to refine the device, focusing on improving its efficiency and reliability, and is exploring commercialisation with a Lincoln-based engineering company.

‘The materials used to make the device are fairly inexpensive and there are manufacturers here in Nebraska with the technology to produce these detectors right now,’ Dowben said.

The detector has applications beyond national security in the US, said physicist Shireen Adenwalla. NASA is reportedly interested in a low mass, thin device like this for their comet landers, which measure the hydrogen content of comets. It also has uses in experimental medical radiation treatments for cancer and for ‘scattering’ experiments performed in basic neutron research.

The research team, all affiliated with UNL’s Centre for Materials Research Analysis, includes Shireen Adenwalla, Physics; Jennifer Brand, Engineering; and Peter Dowben, Physics.

A scientific paper on the device presented by Robertson at a meeting of the International Society for Optical Engineering is said to have generated intense interest and invitations from US national laboratories and European laboratories to present results and participate in research programs.

‘This is something people have been trying to do for more than 38 years and haven’t been able to accomplish,’ Robertson said. ‘We have invented this device and it works very, very well.’