Solid-state material turns visible light into high-energy UV at sunlight intensity, expanding solar energy potential

Two cups of warm water don't make one cup of boiling water. But in the quantum world, multiple low-energy photons can combine to produce a single, higher-energy photon.

Source: [Phys.org](https://phys.org/news/2026-06-solid-state-material-visible-high.html)