USTC team shows how smaller chip size can deliver higher AlGaN-based DUV LED light output power density and peak external quantum efficiency Deep ultraviolet (DUV) light source have numerous valuable applications, including germicidal irradiation, phototherapy, water/air/food sterilization, and optical communication. But while research on AlGaN-based DUV LEDs has made exciting progress, their industrial applications are still in their infancy. This is because of their limited wall plug efficiency (WPE) which is cause by low external quantum efficiency (E...