title: Singular behavior of light-induced space charge in photorefractive media under an ac field
abstract: We show that a photoconductive crystal, placed in a rapidly alternating ac field and exposed to nonuniform light, exhibits singularities of the induced space charge and discontinuities of the corresponding space-charge field. The singularities appear at the local intensity maxima when the curvature of the intensity profile exceeds a certain (often very low) threshold value. We analyze the characteristic features of the singular ac response and consider its possible optical manifestations.
authors.affiliation: Departamento de Fisica de Materiales, C-IV, Universidad Autonoma de Madrid, Cantoblanco, E-28049 Madrid, Spain.
authors.initials: GF
authors.lastname: Calvo
authors.initials: B
authors.lastname: Sturman
authors.initials: F
authors.lastname: Agullo-Lopez
authors.initials: M
authors.lastname: Carrascosa