Optical sensor (IMAGE) California NanoSystems Institute Caption This experimental device uses a 2D semiconductor material developed by Xiangfeng Duan, UCLA professor of chemistry and biochemistry. Credit Dehui Zhang Usage Restrictions none License Original 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.