Jan Masajada
Wrocław University of Technology, Institute of Physics, Faculty Member
- Ferroic Physics, Optical vortex, Microscopy, History of Physics, Optical Tweezers, Philosophy of Science, and 7 moreHistory of Science, History of Mathematics, History of Ideas, Philosophy of Physics, Philosophy of Quantum Mechanics, History and Philosophy of Physics, and Philosophy and history of scienceedit
The Optical Vortex Interferometer (OVI ) uses a regular lattice of optical vortex points. Such lattice can be generated by amplitude division obtained in the modified Mach-Zender set-up. This was reported in our previous papers ([14] -... more
The Optical Vortex Interferometer (OVI ) uses a regular lattice of optical vortex points. Such lattice can be generated by amplitude division obtained in the modified Mach-Zender set-up. This was reported in our previous papers ([14] - [19]). In this work the vortex lattice obtained by wavefront division is reported. We use the opaque screen with three or more holes. The optical vortex lattice obtained using three holes in the screen reveals some special properties as it is in three plane waves version of OVI. We analyze the properties of such lattice as well as lattice generated by four waves and report on possible applications of this particular simple device. The theoretical considerations are illustrated by the experimental results.
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A multi-vortex system nested in a Gaussian beam forms complex paths when it propagates in a free space. We consider a configuration of vortex quadrupole and present a systematic way to control the creation and annihilation of vortex pairs... more
A multi-vortex system nested in a Gaussian beam forms complex paths when it propagates in a free space. We consider a configuration of vortex quadrupole and present a systematic way to control the creation and annihilation of vortex pairs using only one parameter. It is shown that three classes of quadrupole vortex beams can be identified by the number of vortex pairs created or annihilated. The beam symmetry, asymptotic behavior, and stability are analyzed. The main theoretical results are verified experimentally.
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We present the analytical model describing the Gaussian beam propagation through the off axis vortex lens and the set of axially positioned ideal lenses. The model is derived on the base of Fresnel diffraction integral. The model is... more
We present the analytical model describing the Gaussian beam propagation through the off axis vortex lens and the set of axially positioned ideal lenses. The model is derived on the base of Fresnel diffraction integral. The model is extended to the case of vortex lens with any topological charge m. We have shown that the Gaussian beam propagation can be represented by function G which depends on four coefficients. When propagating from one lens to another the function holds its form but the coefficient changes.
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A full comparative analysis of the chain of phase singularities generated when a quasi-plane wave and a Gaussian beam pass a double-phase-ramp (DPR) converter is presented based on the theoretical and experimental data. The overall output... more
A full comparative analysis of the chain of phase singularities generated when a quasi-plane wave and a Gaussian beam pass a double-phase-ramp (DPR) converter is presented based on the theoretical and experimental data. The overall output beam structure includes a system of interrelated optical vortices (OVs) whose linear trajectories form a threedimensional singular skeleton which can be applied for the trapping and guiding of microparticles. An internal structure of each individual phase singularity is characterized by the OV topological charge and by the morphology parameters of the equal intensity ellipses in the OV-core area. The rectilinear equidistant OV trajectories form a chain in the transverse cross section, and their identical morphology parameters can be useful for the applications to metrology and micromanipulation. As a separate result, we consider the DPR-induced transformations of the incident Laguerre-Gaussian beams of the lowest orders and show that the incident multicharged OVs are transformed into small sub-chains of the OVs located in the near-axial region.
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Optical vortices are stable phase singularities, revealing a zero-point in the intensity distribution. The localization of this singular point is of significant importance for any application that relies on vortices and their behavior.... more
Optical vortices are stable phase singularities, revealing a zero-point in the intensity distribution. The localization of this singular point is of significant importance for any application that relies on vortices and their behavior. However, there is still a need for an adaptable, fast, and precise method of singular point localization. Here we show, that the Laguerre-Gaussian transform method can meet those criteria. We compared the performance of this method with two other tracking methods (phase retrieval and weighted centroid) in various conditions. We found out that not only Laguerre-Gaussian transform offers high accuracy, but also does not lose its advantages in the low-contrast regime. The versatility of this algorithm is examined in the optical vortex aberrometry, where we sense two artificially introduced aberrations.
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The Young's double-slit experiment is one of the most popular stories in the history of physics. This paper, like many others, has emerged from the Young's idea. It investigates the diffraction of the plane or spherical... more
The Young's double-slit experiment is one of the most popular stories in the history of physics. This paper, like many others, has emerged from the Young's idea. It investigates the diffraction of the plane or spherical wave produced by three or four small holes in an opaque screen. It was noticed that the interference field contained a lattice of optical vortices which were equivalent to those produced in optical vortex interferometer. The vortex lattice generated by the three holes possessed some unique properties from which the analytical formulae for vortex points position were derived. We also pointed out the differences between our case and the double-slit experiment. Finally, some remarks on possible applications of our arrangement are discussed briefly. These theoretical considerations are illustrated with the use of experimental results.
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Presented work is the next step into creating effective procedure for surface topography reconstruction from Optical Vortex Scanning Microscope data. It focuses on optical vortex behavior due to object introduced by Spatial Light Modulator.
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The dynamics of solute flow in the microscopic chamber can be studied with optical tweezers. A method based on the metallic microbeads trapped in the focused optical vortex beam is proposed. This annular beam of a twisted wavefront exerts... more
The dynamics of solute flow in the microscopic chamber can be studied with optical tweezers. A method based on the metallic microbeads trapped in the focused optical vortex beam is proposed. This annular beam of a twisted wavefront exerts torque on a reflective object placed inside the dark core of the vortex. The induced rotational movement of the bead is sensitive to local viscosity changes in the surrounding medium, for example, during the ongoing dissolution process. Two experimental configurations are described, both relying on tracing the angular velocity of the bead in time. In one-bead configuration, the dynamics of local solute concentration can be studied. In two-bead case, the direction and speed of solute flow can be probed with a spatial resolution of single micrometers. We approach the elementary problem of sucrose dissolution and diffusion in water. The surprising impression of the reverse solute flow was observed. Further experimental investigation led to the discove...
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Remote positioning by precise measurements of lateral displacements of laser beams at large distances is inevitably disturbed by the influence of atmospheric turbulences. Here we propose the use of optical vortices, which exhibit lower... more
Remote positioning by precise measurements of lateral displacements of laser beams at large distances is inevitably disturbed by the influence of atmospheric turbulences. Here we propose the use of optical vortices, which exhibit lower transversal variations at an experimentally validated range of 100 meters. We show the higher precision of the localization of vortex points as compared with standard centroid-based assessment of Gaussian beams. Numerical simulations and experimental measurements show further improvements by averaging of the positions of up to four secondary vortices forming a stable constellation when higher values of the topological charges are used.
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Optical vortex microscope is an optical system in which the beam illuminating the sample contains the optical vortex- a characteristic structure which contains a point of zero amplitude and undefined phase. Such a beam is very sensitive... more
Optical vortex microscope is an optical system in which the beam illuminating the sample contains the optical vortex- a characteristic structure which contains a point of zero amplitude and undefined phase. Such a beam is very sensitive to the phase or amplitude defects which are introduced into it. In this paper we analyze experimentally the response of the optical vortex microscope to the small phase changes introduced into the beam.
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Optical vortices are widely used in optics and photonics, ranging from microscopy and communications to astronomy. However, little work has been done to quantify the quality of scalar optical vortices. Since the quality of an optical... more
Optical vortices are widely used in optics and photonics, ranging from microscopy and communications to astronomy. However, little work has been done to quantify the quality of scalar optical vortices. Since the quality of an optical vortex affects measurements and conclusions derived from their use, development of tools to evaluate the vortex quality is crucial. Moreover, the quality of a vortex strongly depends on the application. Therefore, this work aims to establish metrics for the evaluation of optical vortex quality. We propose to evaluate vortex quality using the following intensity parameters: eccentricity of the intensity distribution, cross-sectional peak-to-valley measurements, cross-sectional peak difference, and the ratio of the ring width to the vortex core diameter (doughnut-ratio). These parameters can be used as a guide for the quality of optical vortices depending on their implementation for specific optical technologies.
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A full comparative analysis of the chain of phase singularities generated when a quasi-plane wave and a Gaussian beam pass a double-phase-ramp (DPR) converter is presented based on the theoretical and experimental data. The overall output... more
A full comparative analysis of the chain of phase singularities generated when a quasi-plane wave and a Gaussian beam pass a double-phase-ramp (DPR) converter is presented based on the theoretical and experimental data. The overall output beam structure includes a system of interrelated optical vortices (OVs) whose linear trajectories form a threedimensional singular skeleton which can be applied for the trapping and guiding of microparticles. An internal structure of each individual phase singularity is characterized by the OV topological charge and by the morphology parameters of the equal intensity ellipses in the OV-core area. The rectilinear equidistant OV trajectories form a chain in the transverse cross section, and their identical morphology parameters can be useful for the applications to metrology and micromanipulation. As a separate result, we consider the DPR-induced transformations of the incident Laguerre-Gaussian beams of the lowest orders and show that the incident m...
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We present the analytical model describing the Gaussian beam propagation through the off axis vortex lens and the set of axially positioned ideal lenses. The model is derived on the base of Fresnel diffraction integral. The model is... more
We present the analytical model describing the Gaussian beam propagation through the off axis vortex lens and the set of axially positioned ideal lenses. The model is derived on the base of Fresnel diffraction integral. The model is extended to the case of vortex lens with any topological charge m. We have shown that the Gaussian beam propagation can be represented by function G which depends on four coefficients. When propagating from one lens to another the function holds its form but the coefficient changes.
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One of the challenges for the Optical Vortex Scanning microscope is to find the effective procedures for surface topography reconstruction. We proposed an experimental setup to support solution of this problem. The Spatial Light Modulator... more
One of the challenges for the Optical Vortex Scanning microscope is to find the effective procedures for surface topography reconstruction. We proposed an experimental setup to support solution of this problem. The Spatial Light Modulator (SLM) is used as a phase object. SLM allows to generate phase disturbance in the range 0-2π, which can be easily introduced into the beam carrying optical vortex. Our system gives an opportunity to measure optical vortex response due to phase modifications introduced by the SLM and investigate vortex sensitivity. We tested how the object position, size affects vortex and position of the vortex point inside the beam.
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We consider a microscopic system in which the focused Gaussian beam with the embedded vortex illuminates the sample. The vortex beam is very sensitive to any imperfections introduced into it. Small defects introduced into the dark area of... more
We consider a microscopic system in which the focused Gaussian beam with the embedded vortex illuminates the sample. The vortex beam is very sensitive to any imperfections introduced into it. Small defects introduced into the dark area of the vortex beam causes the change in its internal structure. We investigate theoretically and experimentally how the small rectangular groove introduced into the beam at the critical plane influence the phase structure of the beam. The analytical model of the setup is provided and following it the scheme for recovering the information about the sample is proposed.
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The composite optical beams being a result of superposition, are a promising way to study the orbital angular momentum and its effects. Their wide range of applications makes them attractive and easily available due to the growing... more
The composite optical beams being a result of superposition, are a promising way to study the orbital angular momentum and its effects. Their wide range of applications makes them attractive and easily available due to the growing interest in the Spatial Light Modulators (SLM). In this paper, we present a simple method for generating composite vortex patterns with high symmetry. Our method is simple, flexible and gives perfectly aligned beams, insensitive to mechanical vibrations. This method is based on the ability to split SLM cells between phase patterns that are to be superposed. This approach allows control of the intensity relation between those structures, enables their rotation and is capable to superpose more than two such structures. In this paper, we examine its ability to produce superposition of two optical vortices by presenting both theoretical and experimental results.
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ABSTRACT Characteristic features of a dynamical system are well-represented by Lyapunov exponents map in a parametric space. The order, quasiperiodic and chaotic regions were identified by the first Lyapunov exponent, whereas in the case... more
ABSTRACT Characteristic features of a dynamical system are well-represented by Lyapunov exponents map in a parametric space. The order, quasiperiodic and chaotic regions were identified by the first Lyapunov exponent, whereas in the case of hyperchaotic regions the sign of the second Lyapunov exponents was also needed. We used this tool to investigate the system governing second-harmonic generation (SHG) of light with a modulated pump as well as a pulsating external field (square-wave). The influence of the pump parameters on dynamics of the generation process is numerically investigated. Chaotic and hyperchaotic behaviour in the system with a weak damping is found in both cases of pumping. This kind of performance of the system can be employed in communication devices. Especially, all-optical switching via second-harmonic generation in a directional coupler is extensively studied. A good diagnostic of dynamical system is the first steep for development of methods of manipulation and control of generated signals.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
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In this work we consider a microscopic optical system in which the beam with an optical vortex illuminates the sample. The sample modifies the geometry of the vortex beam wavefront and the information about it is transferred into the... more
In this work we consider a microscopic optical system in which the beam with an optical vortex illuminates the sample. The sample modifies the geometry of the vortex beam wavefront and the information about it is transferred into the detection plane. It is shown that the beam at the detection plane can be represented by two parts: non-disturbed vortex part and sample part. We propose and test a scheme for recovering the phase changes caused by sample inserted into the vortex beam. The numerical simulations are supported by the experimental work.
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In the paper the simple method of designing and manufacturing the synthetic holograms generating wavefront containing optical vortices is presented. The simple method of numerical analyses of plane wave passing through such holograms is... more
In the paper the simple method of designing and manufacturing the synthetic holograms generating wavefront containing optical vortices is presented. The simple method of numerical analyses of plane wave passing through such holograms is also described.
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The new method for characterization of sidewalls transparent media is presented. The authors introduce optical system based on optical vortex interferometer. Analytical calculation as well as experimental results are shown.
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Optical singularities have focused much of attention for last thirty years. This paper is a short report on applications of optical vortices both actual and potential. Unfortunately the optical vortices are still more promising features... more
Optical singularities have focused much of attention for last thirty years. This paper is a short report on applications of optical vortices both actual and potential. Unfortunately the optical vortices are still more promising features in optical fields than working in real applications. However, there is a hope that they usefulness will grow in the future.
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The regular net of optical vortices generated by the interference of three plane waves can be used for optical measurements. The instrument based on such vortex net is called optical vortex interferometer. In this paper the special... more
The regular net of optical vortices generated by the interference of three plane waves can be used for optical measurements. The instrument based on such vortex net is called optical vortex interferometer. In this paper the special properties of optical field generated by the interference of three plane waves are described. The technological issues of the optical vortex interferometer are also discussed. Finally, two examples of application of the optical vortex interferometer in context of the special properties of the interference field generated by three plane waves, are presented.
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Magnetic fluids (ferrofluids) consist of magnetic nanoparticles (diameter ~10nm) which are dispersed in a liquid, often with the use of surfactants. They were first developed by NASA to address the unique requirements of moving liquid... more
Magnetic fluids (ferrofluids) consist of magnetic nanoparticles (diameter ~10nm) which are dispersed in a liquid, often with the use of surfactants. They were first developed by NASA to address the unique requirements of moving liquid fuel in microgravity conditions. With a help of a holographic optical tweezers, interaction of magnetic nanoparticles with strongly focused laser beam was observed. When the light intensity was high enough, magnetic nanoparticles were removed from the beam center and they formed a dark ring. Creation process lasts less than 330μs and cannot be observed precisely even with ultrafast camera. Such rings exist when the laser beam is affecting the sample and disappear (with a lifespan of 10’th second range) after the laser is switched off. Moreover, when several rings are created simultaneously, complex interactions between them can be observed. In this work, the results of our experiments will be presented with hypotheses about the physical background of such a behavior.
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In this paper the diffraction of Gaussian beam with optical vortex by simple object is considered. The calculations are based on the scalar, near field diffraction integral. The dynamics of the optical vortex within the diffracted wave... more
In this paper the diffraction of Gaussian beam with optical vortex by simple object is considered. The calculations are based on the scalar, near field diffraction integral. The dynamics of the optical vortex within the diffracted wave front is analyzed in particular.
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In this paper we present the Optical Vortex Scanning Microscope (OVSM) in which the new scanning method induced by vortex lens movement is introduced. This method allows to scan the sample in a simple way. The behavior of the vortex... more
In this paper we present the Optical Vortex Scanning Microscope (OVSM) in which the new scanning method induced by vortex lens movement is introduced. This method allows to scan the sample in a simple way. The behavior of the vortex position at the sample plane and phase retrieval algorithm is discussed. The new experimental results confirming the progress in the OVSM building are presented.
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In this paper, it has been shown an apochromatic triplet can be designed without employing special glasses. This possibility is offered when optical system is composed of two lenses, i.e., hybrid and glass ones. Such a system is proposed... more
In this paper, it has been shown an apochromatic triplet can be designed without employing special glasses. This possibility is offered when optical system is composed of two lenses, i.e., hybrid and glass ones. Such a system is proposed and its spherochromatic aberration is determined. Aberration characteristic of the system is compared with that of conventional glass apochromat.
In our work we dealt with holographic lenses recorded on quadrics of revolution. According to third order aberration theory, we derived the expressions for the aberration coefficients in the case of holographic lenses with shifted pupil.... more
In our work we dealt with holographic lenses recorded on quadrics of revolution. According to third order aberration theory, we derived the expressions for the aberration coefficients in the case of holographic lenses with shifted pupil. We show that the aberration coefficients for such system could be expressed by the combination of aberration coefficients for the holographic lens with pupil in contact. We also show that ellipsoidal and hyperboloidal holographic lenses can be replaced by spherical lenses. We examine some possibilities of aberration correction by the substrate geometry and pupil position change.
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ABSTRACT We consider an optical system that consists of a vortex lens and a microscopic objective. The system is illuminated with a He–Ne laser. In our previous work we showed that moving the vortex lens perpendicularly to the optical... more
ABSTRACT We consider an optical system that consists of a vortex lens and a microscopic objective. The system is illuminated with a He–Ne laser. In our previous work we showed that moving the vortex lens perpendicularly to the optical axis makes the optical vortex (introduced by the vortex lens) move inside the focused beam in a characteristic way. We also showed that the vortex trajectory is very sensitive to the position of the observation plane, especially for a large diameter of the incident beam. However, in the microscopic system the aperture is limited by the microscopic objective. In this paper we investigate the propagation of the wide incident laser beam through a vortex lens and then through a microscopic objective with small aperture. We also present a fast interferometric technique for the phase pattern reconstruction of the focused vortex beam.
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ABSTRACT Optical vortices can be used in scanning microscopy. A sample can be scanned just by moving a vortex lens, introducing an optical vortex into a Gaussian beam. This technique seems to be cheap, precise and stable. In this paper... more
ABSTRACT Optical vortices can be used in scanning microscopy. A sample can be scanned just by moving a vortex lens, introducing an optical vortex into a Gaussian beam. This technique seems to be cheap, precise and stable. In this paper the influence of various factors on this scanning technique has been investigated numerically, experimentally and analytically (when possible). Our results show that vortex scanning can be affected by Gaussian beam astigmatism. Other factors (such as optical vortex asymmetry) play a negligible role.
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... Proceedings of SPIE Volume: 2169. Editor(s): Jerzy Nowak; Marek Zajac. Date: 12 October 1994. ... Author(s): Mikhail A. Gan; Dmitriy D. Zhdanov; VV Novoselky. Third order aberrations of a hybrid lens. Author(s): Boguslawa Dubik;... more
... Proceedings of SPIE Volume: 2169. Editor(s): Jerzy Nowak; Marek Zajac. Date: 12 October 1994. ... Author(s): Mikhail A. Gan; Dmitriy D. Zhdanov; VV Novoselky. Third order aberrations of a hybrid lens. Author(s): Boguslawa Dubik; Slawomir Koth; Marek Zajac. ...
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In this paper a phase recovering scheme from the optical vortex microscope is presented. Laguerre-Gaussian beam with the vortex charge equal to one passes through the phase sample and then is detected at the observation plane. The sample... more
In this paper a phase recovering scheme from the optical vortex microscope is presented. Laguerre-Gaussian beam with the vortex charge equal to one passes through the phase sample and then is detected at the observation plane. The sample modifies the internal structure of the vortex beam. The way of measuring such perturbation is presented. Numerical results are confirmed by the experiment.
The regular net of optical vortices can be generated by the interference of three plane waves. The resulting interference field has a number of unique properties, which are discussed in brief. The optical vortex interferometer is a new... more
The regular net of optical vortices can be generated by the interference of three plane waves. The resulting interference field has a number of unique properties, which are discussed in brief. The optical vortex interferometer is a new optical system which is based on such vortex net. The advantages of the optical vortex interferometer, which results form the special properties of the vortex net are also discussed.