Holographic Synthesis of Diffraction Free Beams and Dark Hollow Beams

Since its discovery, holographic techniques had been proved to be one of the most powerful tools for controlling the optical field in almost all the optical areas [1,2,3]. Just to mention some ones, these techniques had been used in the design of hybrid lenses to decrease or avoid aberrations, in optical metrology it had been used to analyze the vibration modes in order to detect potential risks. The recording of the holographic interaction on photo resins it had been possible to design surface roughness, where the statistical features of the surface can be controlled with the parameters of the recording interaction such as time of exposition, angle of recording, wavelength, etc. The influence of these parameters is manifested in the power spectrum associated to the scattered field. A very interesting application of this technique was implemented by West-O’Donnell [4] in order to describe the relation of the scattered field with surface plasmon modes. The experiment was obtained by depositing a metal thin film over the hologram surface. This technique paves the way to implement a two dimensional surface plasmon optics [5,6]. This configuration allows the study of interesting physical properties such as enhanced backscattering also the apparition of satellite peaks in the scattered field [7,8]. This process can be extended by depositing a stack of layers of dielectric thin film-metal thin film, generating in this way a holographic roughness wave guides with application to communication systems. In the holographic context, a very interesting subject consists in the research of novel material of holographic register. In this same context, recently has been reported the recording of the interaction between optical waves on rubidium vapor, which allows the control of light with light [9,10]. Other important materials of holographic register are the photorefractive crystals. In this kind of material, non-linear features can be induced and controlled. For example shift frequency, control of fluorescence time [11,12]. The purpose of this work is to present, in a plain way, the use of a photorefractive crystal as holographic recording material. The hologram consists in the interference between diffraction free beams. The interest in this topic comes from the fact that in the physical optics context, a contemporary topic research consists in the trapping and manipulation of particle conductors or/and dielectrics by means of optical fields also as atom/ion trapping