Fig.2 (IMAGE) Osaka University Caption (a) MQWs sandwiched by the GaN layers are examined by free-space THz emission spectroscopy. (b) Typical terahertz emission waveform from MQW samples. Credit Osaka 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.