Laser particles could provide sharper images of tissues
A new imaging technique developed by scientists at MIT, Harvard University, and Massachusetts General Hospital (MGH) aims to illuminate cellular structures in deep tissue and other dense and opaque materials. Their method uses tiny particles embedded in the material, that give off laser light. The team synthesized these “laser particles” in the shape of tiny chopsticks, each measuring a small fraction of a human hair’s width. The particles are made from lead iodide perovskite — a material that is also used in solar panels, and that efficiently absorbs and traps light. When the researchers shine a laser beam at the particles, the particles light up, giving off normal, diffuse fluorescent light. But if they tune the incoming laser’s power to a certain “lasing threshold,” the particles will instantly generate laser light. The researchers, led by MIT graduate student Sangyeon Cho, demonstrated they were able to stimulate the particles to emit laser light,...