A novel deep red-emitting phosphor KMgLaTeO 6 :Mn 4+ with high thermal stability and quantum yield for w-LEDs: structure, site occupancy and photoluminescence properties

potentially used in w-LEDs is reported, which can be efficiently excited with UV or blue light with a high quantum yield of 68.9% upon 365 nm excitation. More importantly, the luminescence thermal stability of this kind of phosphor shows excellent performance.