Blinking Crystals: How Thousands of Ions Flicker as One
An ordinary light bulb is either on or off. But tiny glowing particles, nanocrystals with rare-earth ions, have so far emitted steady light, like small flashlights. Inside such a crystal, there are thousands of emitting ions, and even if one 'gets tired,' the others keep shining. Therefore, blinking, sharp on-and-off switching, was considered impossible for them.