Light of a certain wavelength can be used to put so - called active materials into motion and control their movement. (sciencedaily.com)
Of these activities, (6), as have indicated, not only plays an essential part in providing active materials, but involves installations capable of generating power. (plosin.com)
It looks like it could be some kind of radio active material left over from some kind of nuclear meltdown! (stokedforsaturday.com)