The ability to detect nuclear radiation effectively and reliably is of unarguable importance in a range of applications, from oil drilling to national security. A common way to detect the gamma rays and subatomic particles emitted by nuclear materials is to use devices based on scintillation, where the rays or particles strike a crystal of sodium iodine (Nal, or similar material) and create flashes of light that are converted to electrical pulses to help identify the type of radiation. The technology has drawbacks, however. The Nal crystal needs to be large to give good resolution, and is usually fragile, difficult to produce and highly vulnerable to humidity. This article presents how researchers at Georga Technology Research Institute, USA, have developed prototype a detector crystal that overcomes these problems. The prototype consists of a glass containing nanoparticles of cerium-doped gadolinium. The gadolinium is essential for scintillation-based detection because of its ability to absorb gamma rays, but it is not an efficient light emitter, so this role is taken by the cerium.
