title: Diffraction-free beams in thin films.
abstract: The propagation and transmission of Bessel beams through nano-layered structures has been discussed recently. Within this framework we recognize the formation of unguided diffraction-free waves with the spot size approaching and occasionally surpassing the limit of a wavelength when a Bessel beam of any order n is launched onto a thin material slab with grazing incidence. On the basis of the plane-wave representation of cylindrical waves, a simple model is introduced providing an exact description of the transverse pattern of this type of diffraction-suppressed localized wave. Potential applications in surface science are put forward for consideration.
authors.affiliation: Departamento de Optica, Universidad de Valencia, Dr. Moliner 50, 46100 Burjassot, Spain. carlos.zapata@uv.es
authors.forename: Carlos J
authors.initials: CJ
authors.lastname: Zapata-Rodríguez
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Miret