Light-Controlled Brake Slows Molecular Motion 300,000 Times, Paving Way for Advanced Nanomachines

Scientists at IOCB Prague have developed a method to dramatically slow random motion within a single molecule using light, reducing the relative rotation of its parts by up to five orders of magnitude—equivalent to a 300,000-fold decrease. This breakthrough, published in a recent study, tackles a fundamental challenge in molecular engineering: thermal energy constantly drives molecules and their components to move unpredictably. By using light as a precise brake, researchers can now control this motion, bringing us closer to building more complex molecular machines. The ability to suppress internal rotation could enable new applications in nanotechnology, such as molecular switches or motors that operate with high precision. While the effect has been demonstrated on a single molecule, the principle may extend to other systems, offering a new tool for controlling the nanoscale world. This research marks a significant step toward taming molecular chaos for practical use.