Lasing cluster (IMAGE) Imperial College London Caption Microparticles clustering around a Janus particle. The dashed line delineates the lasing area, and the pink/yellow lines show the tracks of several microparticles Credit Imperial College London 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.