“Dark” electrons within solid materials may help us learn more about the behaviour of high-temperature superconductors, and perhaps solve other mysteries in material science.
Most of a material’s properties, such as how easily it conducts electricity or reflects light, are dictated by the motion of its electrons. One way of determining these properties is spectroscopy – shining a light on a material and analysing the spectrum of the light that bounces back in order to reveal which frequencies are absorbed or reflected.