Cascade Laser (image) University of Innsbruck Caption This is a schematic picture of a quantum cascade laser. The layers of different semiconductor material constitute the bandstructure shown in the inset. Credit Graphics: Christoph Deutsch Usage Restrictions Only with news coverage on the University of Innsbruck, or the University of Vienna 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.