Nanoscale trick makes “dark excitons” glow 300,000 times stronger

Researchers have found a way to make “dark excitons”—normally invisible quantum states of light—shine dramatically brighter by trapping them inside a tiny gold-nanotube optical cavity. This breakthrough boosts their emission 300,000-fold and allows scientists to switch and tune them with unprecedented precision. The work unlocks new possibilities for ultrafast photonics, on-chip quantum communication, and exploring previously unreachable quantum states in 2D materials.