Frozen waves (FWs) are very interesting particular cases of nondiffracting beams whose envelopes are static and whose longitudinal intensity patterns can be chosen a priori. We present here for the first time (that we know of) the experimental generation of FWs. The experimental realization of these FWs was obtained using a holographic setup for the optical reconstruction of computer generated holograms (CGH), based on a 4-f Fourier filtering system and a nematic liquid crystal spatial light modulator (LC-SLM), where FW CGHs were first computationally implemented, and later electronically implemented, on the LC-SLM for optical reconstruction. The experimental results are in agreement with the corresponding theoretical analytical solutions and hold excellent prospects for implementation in scientific and technological applications.

-In recent times, we experimentally realized a quite efficient modeling of the shape of diffraction-resistant optical beams; thus generating for the first time the so-called Frozen Waves (FW), whose longitudinal intensity pattern can be arbitrarily chosen, within a prefixed space interval of the propagation axis. Such waves possess a host of potential applications: in medicine, biomedical optics, optical tweezers, atom guiding, remote sensing, tractor beams, optical communications or metrology, and other topics in photonic areas. In this work, we extend our theory of FWs -which led to beams endowed with a static envelope-through a dynamic modeling of the FWs, whose shape is now allowed to evolve in time in a predetermined way. And we experimentally create such dynamic FWs in Optics, via a computational holographic technique and a spatial light modulator. Experimental results are here presented for two cases of dynamic FWs, one of the zeroth and the other of higher order, the last one being the most interesting, consisting in a cylindrical surface of light whose geometry changes in space and time.

-In this paper we implement experimentally the spatial shape modelling of nondiffracting optical beams via computer generated holograms on spatial light modulators. The results reported here are the experimental confirmation of the so called Frozen Wave method, developed few years ago. Optical beams of this type can possess potential applications in optical tweezers, medicine, atom guiding, remote sensing, etc..

In this paper, we present the experimental generation of Airy beams via computational and photorefractive holography. Experimental generation of Airy beams using conventional optical components presents several difficulties and are practically infeasible. Thus, the optical generation of Airy beams has been made from the optical reconstruction of a computer generated hologram implemented in a spatial light modulators. In the photorefractive holography technique, being used for the first time to our knowledge, the hologram of an Airy beam is constructed (recorded) and reconstructed (reading) optically in a nonlinear photorefractive medium. The Airy beam experimental realization was made by a setup of computational and photorefractive holography using a photorefractive Bi 12 T iO 20 crystal as holographic recording medium. Airy beams and Airy beam arrays were obtained experimentally as in accordance with the predicted theory; and present excellent prospects for applications in optical trapping and optical communications systems.

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This work presents, for the first time the optical generation of non-diffracting beams via photorefractive holography. Optical generation of non-diffracting beams using conventional optics components is difficult and, in some instances, unfeasible, as it is wave fields given by superposition of non-diffracting beams. It is known that computer generated holograms and spatial light modulators (SLMs) successfully generate such beams. With photorefractive holography technique, the hologram of a non-diffracting beam is constructed (recorded) and reconstructed (reading) optically in a nonlinear photorefractive medium. The experimental realization of a non-diffracting beam was made in a photorefractive holography setup using a photorefractive Bi12SiO20 (BSO) crystal as the holographic recording medium, where the non-diffracting beams, the Bessel beam arrays and superposition of co-propagating Bessel beams (Frozen Waves) were obtained experimentally. The experimental results are in agreement with the theoretically predicted results, presenting excellent prospects for implementation of this technique for dynamical systems at applications in optics and photonics.

In this paper we present a theoretical method, together with its experimental confirmation, to obtain structures of light by connecting diffraction-resistant cylindrical beams of finite lengths and different radii. The resulting "Lego-beams" can assume, on demand, various unprecendent spatial configurations. We also experimentally generate some of them on using a computational holographic technique and a spatial light modulator. Our new, interesting method of linking together various pieces of light can find applications in all fields where structured light beams are needed, in particular such as optical tweezers, e.g. for biological manipulations, optical guiding of atoms, light orbital angular momentum control, holography, lithography, non-linear-optics, interaction of electromagnetic radiation with Bose-Einstein condensates, and so on, besides in general the field of Localized Waves (non-diffracting beams and pulses). [MZR] ( * ) Visiting c/o Decom, Unicamp, by a PVE fellowship of CAPES (Brazil) arXiv:1712.01118v2 [physics.optics] 5 Apr 2018Structured Light [1,2,3, 4,5,6] has been more and more studied, and applied in various sectors, like optical tweezers [7,8,9,10,11,12,13,14,15,16,17], optical guiding of atoms [18,19,20,21,22,23,24], imaging [25], light orbital angular momentum control and applications [26,27,28,29,30,31], and photonics in general.A rather efficient method to model longitudinally the intensity of non-diffracting beams is by the so-called Frozen Waves (FWs) [1,2,3,32,33,34,35,36], obtained from superpositions of co-propagating Bessel beams, endowed with the same frequency and order. The resulting diffraction resistant beam, with a longitudinal intensity shape freely chosen a priori, may then propagate, remaining confined, along the propagation axis z, or over a cylindrical surface (depending on the order of the constituting Bessel beams), while its "spot" size, and the cylindrical surface radius, can be as well chosen a priori. In this way, it is possible to construct, e.g., cylindrical beams whose static envelopes possess non-negligible energy density in finite, well-defined spatial intervals only: so that they can be regarded as segments or cylindrical pieces of light.Aiming also at a greater control on the beam transverse shape, another method was recently proposed [24,26], where different-order FW-type beams are superposed, which possess appreciable intensities along different, but consecutive, space intervals: So that one ends with cylindrical structures of light endowed with different radii and located in different positions along the z axis. This new method resulted efficient, incidentally, also for controlling the orbital angular momentum along the propagation axis [26].Anyway, and interestingly enough, it is possible to join together in the same way even two FW-type beams bearing the same order, by getting again a structure with two different-radius cylinders, each one in its own space interval. To this aim, it is sufficient that each equal-order FW possesses a different value of ...

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