Photonic Cavity (IMAGE) Technical University of Denmark Caption Illustration of the core of the photonic cavity that was fabricated as two halves that assembled themselves into one unit. The cavity confines light inside the gap, which is only a few atoms wide as indicated in the field of view of the magnifying glass. Illustration by Thor A. S. Weis. Credit Illustration by Thor A. S. Weis. Usage Restrictions None with due credit and reference to DOI. 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.