First Blue LED Emission From a Perovskite

Researchers in California have extended the spectral range of perovskite light-emitting diodes into the blues. How did they do it? By cracking the mystery of why the optical and electronic properties of the materials change when current flows through them. Painstaking measurements revealed that current-induced heating deformed cells in the semiconductor crystals. That observation enabled the team to make the first single-crystal perovskite diodes, says group leader Peidong Yang, a chemistry professor at the University of California at Berkeley.