Illustration (IMAGE) Moscow Institute of Physics and Technology Caption Light emission resulting from a mutual annihilation of electrons and holes is the operating principle of semiconductor lasers. Credit Elena Khavina/MIPT Press Office 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.