Eli portrait (IMAGE) Utah State University Caption Eli Yablonovitch is the father of the phototonic bandgap and a professor emeritus at UC Berkeley. He will be speaking at USU on April 25. Credit UC Berkeley Usage Restrictions N/A 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.