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Michel Zamboni-Rached

Publications and source records attributed to Michel Zamboni-Rached.

At least 19 recordsLinked to original sources
arXiv2026

Structured light sheets

In this work, we present a simple, exact, and fully analytical method for generating light sheets parallel to the propagation direction, with amplitude and phase envelopes structured on demand. We validate the approach theoretically and experimentally by imprinting images onto light sheets, and we compare the theoretical performance with that obtained using an alternative strategy based on arrays of Frozen Waves (FWs). In this context, the proposed method provides a more direct and flexible control of the field envelopes on the light sheets, resulting in higher-fidelity reconstructions than those achieved with FW-based approaches. The method thus offers a versatile framework for structured light-sheet generation, with potential applications in optical manipulation, microscopy, and 3D holographic imaging.

physics.optics↗
arXiv2024

Shaping High-Order Diffraction-Free Beams Through Continuous Superposition of Bessel Beams

Recognized for their non-diffracting properties, Bessel beams can be conveniently combined to generate the so-called Frozen Waves, which are monochromatic beams endowed with topological charge and whose longitudinal intensity pattern can be shaped according to a previously chosen function. Continuous superposition of Bessel beams is specially suitable for micrometer-scale domains, being highly relevant for applications in optical tweezers, particle trapping and atom guidance. Previous studies have successfully constructed micrometer Frozen Wave solutions with null topological charge; nevertheless, some challenges persist in obtaining exact solutions when dealing with higher topological charge values (i.e., higher-order micrometer Frozen Waves). Typically, a topological charge raising operator is used to elevate the order; however, such solutions face significant issues when the orders become excessively high. In this paper, based in continuous superposition of higher order Bessel beams, we develop a novel analytic and exact solution for higher-order micrometer Frozen Waves, so obtaining a method for modeling the intensity of beams with arbitrary topological charge within micrometer spatial domains. We also investigate the behavior of the electric field's longitudinal component in such highly non-paraxial regimes through a vectorial treatment.

physics.optics↗
arXiv2023

Microstructured optical beams with azimuthal polarization in stratified absorbent media

We present an analytical method to achieve highly non-paraxial, azimuthally polarized structured beams that, when propagating through an absorbing stratified media, can assume in the last semi-infinite layer approximately any desired longitudinal intensity pattern within spatial regions few times larger than the wavelength. The possibility of managing the properties of a highly non-paraxial beam under adverse conditions, such as multiple reflections in stratified structures and energy loss to the material media, may be of great importance in many different optical applications, like trapping and micro-manipulation, remote sensing, thin films, medical devices, medical therapies and so on.

physics.optics↗
arXiv2021

Carving light beams

Some years after the appearance of the so-called non-diffracting beams, there was the development of methods capable of structuring them spatially, being the so called Frozen Waves method the first and, perhaps, the most efficient one. That method allowed modelling the longitudinal intensity pattern of non-diffracting beams, being, however, little efficient in controlling their transverse spatial pattern, granting only the possibility of choosing their transverse dimensions, which remain invariant throughout the propagation. In this work, we have extended the Frozen Wave method in such a way to control, in addition to the longitudinal pattern, the transverse beam structure along the propagation. The new transversally and longitudinally structured beams can have potential applications in areas such as photonics, optical manipulation, optical atom guidance, lithography, etc..

physics.optics↗
arXiv2020

Experimental optical trapping of micro-particles with Frozen Waves

This work presents the first optical trapping experimental demonstration of micro-particles with Frozen Waves. Frozen Waves are an efficient method to model longitudinally the intensity of non-diffracting beams obtained by superposing co-propagating Bessel beams with the same frequency and order. The experimental setup of a holographic optical tweezers using spatial light modulators has been assembled and optimized. We investigate the optical force distribution acting on micro-particles of two types of Frozen Waves.The results show that it is possible to obtain greater stability for optical trapping using Frozen Waves. The significant enhancement in trapping geometry from this approach shows promising applications for optical tweezers, micro-manipulations over a broad range.

physics.optics↗
arXiv2018

Fusion Between Frozen-Wave-Type Beams and Airy-Type Pulses: Diffraction-Dispersion-Attenuation Resistant Vortex Pulses in Absorbing Media

In this paper we perform a fusion between two important theoretical methodologies, one related to the Frozen Wave beams, which are non-diffracting beams whose longitudinal intensity pattern can be chosen a priori in an medium (absorbing or not), and the other related to the Airy-Type pulses, which are pulses resistant to dispersion effects in dispersive materials. As a result, a new method emerges, capable of providing vortex pulses resistant to three concomitant effects, i.e.: diffraction, dispersion and attenuation; while concurrently the spatial variation of the wave intensity along its axis of propagation can be engineered at will. The new approach can be seen as a generalization of the Localized Waves theory in the paraxial regime and the new pulses can have potential applications in different fields such as optics communications, nonlinear optics, micromanipulation, and so on.

physics.optics↗
arXiv2018

A simple and analytical method for controlling the trajectory and multifurcation of optical beams

In this paper it is developed a simple, analytical and very efficient method capable to provide control of optical beam's intensity over an arbitrary curvilinear (planar) trajectory. The same method also provides the possibility of managing multifurcations of the optical beam. The results presented here can have valuable applications in fields like optical tweezers, optical lithography, atom optical guiding, structured light, etc..

physics.optics↗
arXiv2018

Modelling the longitudinal intensity pattern of diffraction resistant beams in stratified media

In this paper, we study the propagation of the Frozen Wave type beams through non-absorbing stratified media and develop a theoretical method capable to provide the desired spatially shaped diffraction resistant beam in the last material medium. In this context, we also develop a matrix method to deal with stratified media with large number of layers. Additionally, we undertake some discussion about minimizing reflection of the incident FW beam on the first material interface by using thin films. Our results show that it is indeed possible to obtain the control, on demand, of the longitudinal intensity pattern of a diffraction resistant beam even after it undergoes multiple reflections and transmissions at the layer interfaces. Remote sensing, medical and military applications, noninvasive optical measurements, etc., are some fields that can be benefited by the method here proposed.

physics.optics↗
arXiv2017

Structured Light by linking together diffraction-resistant spatially shaped beams: "LEGO-BEAMS"

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 unprecedented 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 the field in general of Localized Waves (non-diffracting beams and pulses).

physics.optics↗
arXiv2017

Arbitrary control of the polarization and intensity profiles of diffraction-attenuation-resistant beams along their propagation direction

We report on the theory and experimental generation of a class of diffraction-attenuation-resistant beams with state of polarization (SoP) and intensity that can be controlled on demand along the propagation direction. This is achieved by a suitable superposition of Bessel beams, whose parameters are systematically chosen based on closed-form analytic expressions provided by the Frozen Waves (FWs) method. Using an amplitude-only spatial light modulator, we experimentally demonstrate three scenarios. In the first, the SoP of a horizontally polarized beam evolves to radial polarization and is then changed to vertical polarization, with the beam intensity held constant. In the second, we simultaneously control the SoP and the longitudinal intensity profile, which was chosen such that the beam's central ring can be switched-off over predefined space regions, thus generating multiple foci with different SoP and at different intensity levels along the propagation. Finally, the ability to control the SoP while overcoming attenuation inside lossy fluids is shown experimentally for the first time in the literature (to the best of our knowledge). Therefore, we envision our proposed method to be of great interest for many applications, such as optical tweezers, atom guiding, material processing, microscopy, and optical communications.

physics.optics↗
arXiv2017

Shaping the longitudinal intensity pattern of Cartesian beams in lossless and lossy media

Several applications, such as optical tweezers and atom guiding, benefit from techniques that allow the engineering of optical fields' spatial profiles, in particular their longitudinal intensity patterns. In cylindrical coordinates, methods such as Frozen Waves allow an advanced control of beams' characteristics, but in Cartesian coordinates there is no analogous technique. Since Cartesian beams may also be useful for applications, we develop here a method to modulate on-demand the longitudinal intensity pattern of any (initially) unidimensional Cartesian beam with concentrated wavevector spectrum, thus encompassing all paraxial unidimensional beams. To this end, we write the total beam as a product of two unidimensional beams and explore the degree of freedom provided by the additional Cartesian coordinate. While in the plane where this coordinate is zero the chosen unidimensional beam keeps its structure with the additional desired intensity modulation, a sinusoidal-like oscillation appears in the direction of this variable and creates a spot whose size is tunable. Examples with Gaussian and Airy beams are presented and their corresponding experimental demonstrations are performed to show the validity of the method.

physics.optics↗
arXiv2017

Nonparaxial Cartesian and azimuthally symmetric waves with concentrated wavevector and frequency spectra

In this paper, we develop a theoretical analysis to efficiently handle superpositions of waves with concentrated wavevector and frequency spectra, allowing an easy analytical description of fields with interesting transverse profiles. First, we analyze an extension of the paraxial formalism that is more suitable for superposing these types of waves, as it does not rely on the use of coordinate rotations combined with paraxial assumptions. Second, and most importantly, we leverage the obtained results to describe azimuthally symmetric waves composed of superpositions of zero-order Bessel beams with close cone angles that can be as large as desired, unlike in the paraxial formalism. Throughout the paper, examples are presented, such as Airy beams with enhanced curvatures, nonparaxial Bessel-Gauss beams and Circular Parabolic-Gaussian beams (which are based on the Cartesian Parabolic-Gaussian beams), and experimental data illustrates interesting transverse patterns achieved by superpositions of beams propagating in different directions.

physics.optics↗
arXiv2016

Longitudinal patterning of twisted light

Light beams with azimuthal phase dependence [$exp(i \ell\phi)$] carry orbital angular momentum (OAM) which differs fundamentally from spin angular momentum (SAM) associated with polarization. Striking difference between the two momenta is manifested in the allowable values: where SAM is limited to $\hbar k_0$ per photon, the OAM has unbounded value of $\ell\hbar$ per photon ($\ell$ is integer), thus dramatically exceeding the value of SAM \cite{Ref1,Ref2, Ref3}. OAM has thus been utilized in optical trapping \cite{Ref4}, imaging\cite{Ref2}, and material processing \cite{Ref5}. Furthermore, the unbounded degrees-of-freedom in OAM states have been deployed in data communications \cite{Ref6}. Here, we report an \textit{exceptional} behavior for a class of light beams---known as Frozen Waves (FWs)---whose intensity and azimuthal phase profiles can be controlled along the propagation direction, at will. Accordingly, we generate rotating light patterns that can change their sense of rotation and order of phase twist with propagation. Manipulating OAM along the beam axis can open new directions in optical science and its applications.

physics.optics↗
arXiv2015

Optical generation of non-diffracting beams via photorefractive holography

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.

physics.optics↗
arXiv2015

Modeling of Space-Time Focusing of Localized Nondiffracting Pulses

In this paper we develop a method capable of modeling the space-time focusing of nondiffracting pulses. The new pulses can possess arbitrary peak velocities and, in addition to being resistant to diffraction, can have their peak intensities and focusing positions chosen a priori. More specifically, we can choose multiple locations (spatial ranges) of space/time focalization; also, the pulse intensities can be chosen in advance. The pulsed wave solutions presented here can have very interesting applications in many different fields, such as free-space optical communications, remote sensing, medical apparatus, etc.

physics.optics↗
arXiv2015

Production of Dynamic Frozen Waves: Controlling shape, location (and speed) of diffraction-resistant beams

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.

physics.optics↗
arXiv2015

Diffraction Resistant Scalar Beams Generated by a Parabolic Reflector and a Source of Spherical Waves

In this work, we propose the generation of diffraction resistant beams by using a parabolic reflector and a source of spherical waves positioned at a point slightly displaced from its focus (away from the reflector). In our analysis, considering the reflector dimensions much greater than the wavelength, we describe the main characteristics of the resulting beams, showing their properties of resistance to the diffraction effects. Due to its simplicity, this method may be an interesting alternative for the generation of long range diffraction resistant waves.

physics.optics↗