Anti-diffracting beams through the diffusive optical nonlinearity

摘要

Anti-diffraction is a theoretically predicted nonlinear opticaludphenomenon that occurs when a light beam spontaneously focalizes independently of its intensity. We observe anti-diffracting beams supported by the peak-intensity-independent diffusive nonlinearity that are able to shrink below their diffraction-limited size in photorefractive lithium-enriched potassium-tantalate-niobate (KTN:Li).