When an electron travels through a polar crystalline solid, its negative charge attracts the positively charged atomic cores, causing the surrounding crystal lattice to deform. The electron and lattice distortion then move together through the material—like a single object. Physicists call these quasiparticles polarons. A team led by Professor Jochen Feldmann from LMU has succeeded in tracking the extremely brief formation process of this object for the first time, using an ultrafast imaging method.