Dark Points Outpace Light, Boosting Atomic-Scale Imaging
Using ultrafast transmission electron microscopy and Ramsay interferometry to track optical phase singularities in hexagonal boron nitride polaritons, researchers observed dark points accelerating to superluminal speeds within the light field, confirming a 50-year-old prediction by Nye and Berry. The measurements reveal universal space–time dynamics of these singularities and could enhance super-resolution microscopy and information encoding in orbital angular momentum, with future work on 3D line singularities and other 2D materials.