GaN:Eu LED (IMAGE) Lehigh University Caption The top row is a GaN:Eu LED, which can be tuned from red-yellow due to red and green light mixing from different Eu states. The middle and bottom rows are of a GaN:Eu LED with additionally added Si/Mg, which adds blue emission. Each picture is under a different current injection/filtering condition. Credit West Chester University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.