Radially Self-Accelerating Beams
  We report on optical non-paraxial beams that exhibit a self-accelerating behavior in radial direction. Our theory shows that those beams are solutions to the full scalar Helmholtz equation and that they continuously evolve on spiraling trajectories. We provide a detailed insight into the theoretical origin of the beams and verify our findings on an experimental basis. 
Christian Vetter, Toni Eichelkraut, Marco Ornigotti, Markus Gr\"afe   and Alexander Szameit
physics.optics