SEM of Lasing/Anti-Lasing Device (IMAGE) DOE/Lawrence Berkeley National Laboratory Caption Scanning electron microscope image of the single device capable of lasing and anti-lasing. Indium gallium arsenide phosphide (InGaAsP) material functions as the gain medium, while the chromium (Cr) and germanium (Ge) structures introduce the right amount of loss to satisfy the condition of parity-time symmetry that is required for lasing and anti-lasing. Credit Zi Jing Wong/UC Berkeley Usage Restrictions All rights reserved. Commercial use prohibited. 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.