The World's Smallest Engine (IMAGE) Trinity College Dublin Caption The world's smallest engine works due to its intrinsic spin, which converts heat absorbed from laser beams into oscillations, or vibrations, of the trapped ion. Credit Professor Goold, Trinity College Dublin. 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.