Smiley Face (IMAGE) DOE/Lawrence Berkeley National Laboratory Caption An electron beam placed at a series of locations on a sheet of twisted hBN intensifies the light emission from each location. The brightness depends on how long the beam sits at a given point, or the electron flux delivered to that point. The result is an illuminated pattern. Credit Su et al. 2022 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.