Alberto Tufaile - Academia.edu (original) (raw)

Papers by Alberto Tufaile

Revista Brasileira de Ensino de Física

Estudamos a evolução temporal da temperatura no sensor de um termômetro digital do tipo espeto no... more Estudamos a evolução temporal da temperatura no sensor de um termômetro digital do tipo espeto no qual ocorre evaporação de água de torneira ou álcool 70° (etanol). Apresentamos um modelo teórico com base no princípio da conservação da energia, no qual a diferença de temperatura do sensor em relação à ambiente tem duas componentes exponenciais, sendo uma proporcional ao calor perdido devido à evaporação do líquido que molha a haste do termômetro e a outra exponencial proporcional ao calor recebido do ar ambiente, nos momentos que a haste do sensor está mais fria que o ambiente. Analisamos quantitativamente o fenômeno ajustando a equação teórica aos dados experimentais. Para confirmar o comportamento exponencial relacionado à evaporação, medidos a variação de massa durante a evaporação. O modelo proposto funciona muito bem para a evaporação de etanol. O material experimental mínimo necessário para o estudo quantitativo proposto é um termômetro digital de espeto, uma pisseta com álcoo...

Our goal with this book is to show our personal experience with the use of Ferrocell. The use of ... more Our goal with this book is to show our personal experience with the use of Ferrocell. The use of Ferrocell, also known as Ferrolens, is a way to encourage the study of magneto-optics in a more intuitive way. Ferrocell is a device based on a thin film of nanoparticles, which when subjected to a magnetic field, can interact the light propagation. At the beginning of most chapters there are questions that guide the reader, and at the ending of each chapter, there is a list of references related to the same chapter. Some of our articles that are references in these chapters are open access and we strongly encourage you to also consider the references in these articles as an important part of understanding this book. Some topics in this book presented in a chapter and can be taken up in a different perspective in the following chapters. As interest in Ferrocell goes far beyond the community of physicists, material scientists and engineers, we try to illustrate the main concepts through i...

Air bubble formation was studied with a nozzle submerged in a water/glycerol solution [1]. The in... more Air bubble formation was studied with a nozzle submerged in a water/glycerol solution [1]. The influence of the pneumatic system was studied using the air flow rate as the control parameter. We have observed period-adding routes and some attractors without external applied perturbation [2]. We have also studied the period-adding bifurcation by a slightly change of the control parameter around the bifurcation values. Changing a tube placed between the control valve and the nozzle, we could study the influence of the tube length on the periodic orbits found as the control parameter change. At this work we present bifurcation diagrams for different tube lengths. Similar behavor was found in different dynamic systems and was already found the evidence of homoclinic behavior in those systems [3,4]. Some similarities between those systems and our experimental results are lso presented by bifurcation diagrams and return maps comparison. References: [1] Tufaile, A

Frontiers in Optics + Laser Science 2021, 2021

We have observed the formation of light rings in a thin film of ferrofluid subjected to a magneti... more We have observed the formation of light rings in a thin film of ferrofluid subjected to a magnetic field, and associated them with horocycles.

13th Chaotic Modeling and Simulation International Conference, 2021

We are presenting experimental results and simulations of dynamical systems using magneto-optics.... more We are presenting experimental results and simulations of dynamical systems using magneto-optics. These light patterns are obtained by the observation of a thin film of ferrofluid in the presence of a magnetic in the presence of a magnetic field.

We studied the effects of image formation in a device known as Ferrocell, which consists of a thi... more We studied the effects of image formation in a device known as Ferrocell, which consists of a thin film of a ferrofluid solution between two glass plates subjected to an external magnetic field in the presence of a light source. Following suggestions found in the literature, we compared the Ferrocell light scattering for some magnetic field configurations with the conical scattering of light by thin structures found in foams known as Plateau borders, and we discuss this type of scattering with the concept of diffracted rays from the Geometrical Theory of Diffraction. For certain magnetic field configurations, a Ferrocell with a point light source creates images of circles, parabolas, and hyperboles. We interpret the Ferrocell images as analogous to a Möbius transformation by inversion of the magnetic field. The formation of circles through this transformation is known as horocycles, which can be observed directly in the Ferrocell plane.

Ciências Exatas e da Terra: Conhecimentos Estratégicos para o Desenvolvimento do País, 2020

Fifteenth Conference on Education and Training in Optics and Photonics: ETOP 2019, 2019

In Brazil, we've perceived that there is resistance to the learning of Optics by students who are... more In Brazil, we've perceived that there is resistance to the learning of Optics by students who are not from the area of physics. The traditional way of teaching optics requires a prior knowledge of calculus that is not easy to students of the natural sciences. In order to solve this problem, we have developed an experimental optics discipline for undergraduate students in nature sciences: Concepts in Experimental Optics (Conceitos de Óptica Experimental, EACH-USP). This course is divided into three parts: (I) The Origin of Light, (II) The Path of Light and (III) The Light Destination. In the first part, we work with light emission spectra, continuum and ray spectra, using spectral lamps and everyday lamps. The second part presents the concepts and applications of Geometrical Optics and Wave Optics, including Geometrical Theory of Diffraction. The third part is about the absorption of light by matter with application in light detectors and photosynthesis. In the first lesson, we introduce the subject of human vision functioning, for interpretation of colors. The human vision is resumed in the third part. In Geometrical Optics we use images from works by artists such as René Magritte and M. C. Escher to encourage discussion about imaging. The emphasis of the discipline is to understand natural phenomena with as few calculations as possible and to encourage the demonstrations that can be made with everyday objects. We have taught this subject twice, 2017 and 2018, totaling 27 approved students with an average grade of approximately 87%.

13th Chaotic Modeling and Simulation International Conference, 2021

Condensed Matter, 2022

We studied the polarized light patterns obtained using a thin film of ferrofluid subjected to an ... more We studied the polarized light patterns obtained using a thin film of ferrofluid subjected to an applied magnetic field. We obtained patterns of polarized light with magnetic field configurations between parallel plates, monopolar, tetrapolar, and hexapolar, and studied how polarized light varies for different intensities and orientations of the applied magnetic field. Using the Jones calculus, we explored the key optical properties of this system and how these properties relate to the applied magnetic field. We have observed general aspects of polarized light obtained by transmission in a Ferrocell using polariscopes and analyzing the resulting Jones vector, such as the formation and rotation of dark bands known as isogyres. We suggest that in a thin film of ferrofluid as in a Ferrocell, two effects occur. The primary effect is dichroism, which is more sensitive to the component of the magnetic field in the direction parallel to the film plane. The secondary effect is the birefring...

Condensed Matter, 2021

We studied the effects of image formation in a device known as Ferrocell, which consists of a thi... more We studied the effects of image formation in a device known as Ferrocell, which consists of a thin film of a ferrofluid solution between two glass plates subjected to an external magnetic field in the presence of a light source. Following suggestions found in the literature, we compared the Ferrocell light scattering for some magnetic field configurations with the conical scattering of light by thin structures found in foams known as Plateau borders, and we discuss this type of scattering with the concept of diffracted rays from the Geometrical Theory of Diffraction. For certain magnetic field configurations, a Ferrocell with a point light source creates images of circles, parabolas, and hyperboles. We interpret the Ferrocell images as analogous to a Möbius transformation by inversion of the magnetic field. The formation of circles through this transformation is known as horocycles, which can be observed directly in the Ferrocell plane.

The dynamics of bubble, drop, and foam formation can present chaotic behavior. Under certain cond... more The dynamics of bubble, drop, and foam formation can present chaotic behavior. Under certain conditions these systems present routes to chaos such as period doubling, period adding, or intermittency. In addition to these aspects, some interesting emergent types of fragile objects can be observed, such as antibubbles.

Frontiers in Optics / Laser Science, 2020

We present results of the laser scattering in some structures of foams known as Plateau borders. ... more We present results of the laser scattering in some structures of foams known as Plateau borders. The light patterns are Parlaseric Circle with Laser Dogs and Horus Eye. Parlaseric Circle is due to conical diffraction.

11th Chaotic Modeling and Simulation International Conference, 2019

We have developed a magneto-optical system which simulates the stability of fixed points and the ... more We have developed a magneto-optical system which simulates the stability of fixed points and the trajectories of orbits present in dynamical systems. The question of stability is significant because a real-world system is constantly subject to small perturbations, and these orbits can be observed with a Ferrocell, a device using ferrofluid, which is a superparamagnetic fluid obtained with a kind of colloid containing surfactant coated nanometer ferromagnetic particles dispersed in a carrier liquid, and this device can be used in applications of optical effects. Our magneto-optical system is based in a Hele-Shaw cell containing ferrofluid, illuminated with an external light source, such as LED. By injecting a light propagating along the in-plane direction of the liquid film, the orbits can be observed, in a way that we can bend the light. The trajectories of the orbits are obtained by the diffracted light, which consists of light patterns, and these light patterns are related to Faraday effect, linear dichroism, and linear birefringence. The diffraction pattern is different from that produced by a wire because there are no fringes in these light patterns, and the absence of well-defined spacing between the fringes indicates the existence of multiple diffraction. Under certain circumstances, these light patterns can have the same properties of the force lines of magnetic fields. The main idea of this work is to propose a device applied to non-linear systems, based on magneto-photonics. We present the patterns obtained for different magnetic fields simulating dynamical systems.

Frontiers in Optics + Laser Science APS/DLS, 2019

We have investigated the light patterns in a thin film of ferrofluid subjected to a magnetic fiel... more We have investigated the light patterns in a thin film of ferrofluid subjected to a magnetic field, in a device known as Ferrolens. We observed magnetic contours and light polarization effects.

Frontiers in Optics + Laser Science APS/DLS, 2019

We developed some optical elements to observe some peculiar laser patterns. We obtained the Spira... more We developed some optical elements to observe some peculiar laser patterns. We obtained the Spiralbow and the involute of a circle. We designed a Hyperbolic Prism and obtained the pattern know as the Parlaseric Circle.

Revista Brasileira de Ensino de Física

Estudamos a evolução temporal da temperatura no sensor de um termômetro digital do tipo espeto no... more Estudamos a evolução temporal da temperatura no sensor de um termômetro digital do tipo espeto no qual ocorre evaporação de água de torneira ou álcool 70° (etanol). Apresentamos um modelo teórico com base no princípio da conservação da energia, no qual a diferença de temperatura do sensor em relação à ambiente tem duas componentes exponenciais, sendo uma proporcional ao calor perdido devido à evaporação do líquido que molha a haste do termômetro e a outra exponencial proporcional ao calor recebido do ar ambiente, nos momentos que a haste do sensor está mais fria que o ambiente. Analisamos quantitativamente o fenômeno ajustando a equação teórica aos dados experimentais. Para confirmar o comportamento exponencial relacionado à evaporação, medidos a variação de massa durante a evaporação. O modelo proposto funciona muito bem para a evaporação de etanol. O material experimental mínimo necessário para o estudo quantitativo proposto é um termômetro digital de espeto, uma pisseta com álcoo...

Our goal with this book is to show our personal experience with the use of Ferrocell. The use of ... more Our goal with this book is to show our personal experience with the use of Ferrocell. The use of Ferrocell, also known as Ferrolens, is a way to encourage the study of magneto-optics in a more intuitive way. Ferrocell is a device based on a thin film of nanoparticles, which when subjected to a magnetic field, can interact the light propagation. At the beginning of most chapters there are questions that guide the reader, and at the ending of each chapter, there is a list of references related to the same chapter. Some of our articles that are references in these chapters are open access and we strongly encourage you to also consider the references in these articles as an important part of understanding this book. Some topics in this book presented in a chapter and can be taken up in a different perspective in the following chapters. As interest in Ferrocell goes far beyond the community of physicists, material scientists and engineers, we try to illustrate the main concepts through i...

Air bubble formation was studied with a nozzle submerged in a water/glycerol solution [1]. The in... more Air bubble formation was studied with a nozzle submerged in a water/glycerol solution [1]. The influence of the pneumatic system was studied using the air flow rate as the control parameter. We have observed period-adding routes and some attractors without external applied perturbation [2]. We have also studied the period-adding bifurcation by a slightly change of the control parameter around the bifurcation values. Changing a tube placed between the control valve and the nozzle, we could study the influence of the tube length on the periodic orbits found as the control parameter change. At this work we present bifurcation diagrams for different tube lengths. Similar behavor was found in different dynamic systems and was already found the evidence of homoclinic behavior in those systems [3,4]. Some similarities between those systems and our experimental results are lso presented by bifurcation diagrams and return maps comparison. References: [1] Tufaile, A

Frontiers in Optics + Laser Science 2021, 2021

We have observed the formation of light rings in a thin film of ferrofluid subjected to a magneti... more We have observed the formation of light rings in a thin film of ferrofluid subjected to a magnetic field, and associated them with horocycles.

13th Chaotic Modeling and Simulation International Conference, 2021

We are presenting experimental results and simulations of dynamical systems using magneto-optics.... more We are presenting experimental results and simulations of dynamical systems using magneto-optics. These light patterns are obtained by the observation of a thin film of ferrofluid in the presence of a magnetic in the presence of a magnetic field.

We studied the effects of image formation in a device known as Ferrocell, which consists of a thi... more We studied the effects of image formation in a device known as Ferrocell, which consists of a thin film of a ferrofluid solution between two glass plates subjected to an external magnetic field in the presence of a light source. Following suggestions found in the literature, we compared the Ferrocell light scattering for some magnetic field configurations with the conical scattering of light by thin structures found in foams known as Plateau borders, and we discuss this type of scattering with the concept of diffracted rays from the Geometrical Theory of Diffraction. For certain magnetic field configurations, a Ferrocell with a point light source creates images of circles, parabolas, and hyperboles. We interpret the Ferrocell images as analogous to a Möbius transformation by inversion of the magnetic field. The formation of circles through this transformation is known as horocycles, which can be observed directly in the Ferrocell plane.

Ciências Exatas e da Terra: Conhecimentos Estratégicos para o Desenvolvimento do País, 2020

Fifteenth Conference on Education and Training in Optics and Photonics: ETOP 2019, 2019

In Brazil, we've perceived that there is resistance to the learning of Optics by students who are... more In Brazil, we've perceived that there is resistance to the learning of Optics by students who are not from the area of physics. The traditional way of teaching optics requires a prior knowledge of calculus that is not easy to students of the natural sciences. In order to solve this problem, we have developed an experimental optics discipline for undergraduate students in nature sciences: Concepts in Experimental Optics (Conceitos de Óptica Experimental, EACH-USP). This course is divided into three parts: (I) The Origin of Light, (II) The Path of Light and (III) The Light Destination. In the first part, we work with light emission spectra, continuum and ray spectra, using spectral lamps and everyday lamps. The second part presents the concepts and applications of Geometrical Optics and Wave Optics, including Geometrical Theory of Diffraction. The third part is about the absorption of light by matter with application in light detectors and photosynthesis. In the first lesson, we introduce the subject of human vision functioning, for interpretation of colors. The human vision is resumed in the third part. In Geometrical Optics we use images from works by artists such as René Magritte and M. C. Escher to encourage discussion about imaging. The emphasis of the discipline is to understand natural phenomena with as few calculations as possible and to encourage the demonstrations that can be made with everyday objects. We have taught this subject twice, 2017 and 2018, totaling 27 approved students with an average grade of approximately 87%.

13th Chaotic Modeling and Simulation International Conference, 2021

Condensed Matter, 2022

We studied the polarized light patterns obtained using a thin film of ferrofluid subjected to an ... more We studied the polarized light patterns obtained using a thin film of ferrofluid subjected to an applied magnetic field. We obtained patterns of polarized light with magnetic field configurations between parallel plates, monopolar, tetrapolar, and hexapolar, and studied how polarized light varies for different intensities and orientations of the applied magnetic field. Using the Jones calculus, we explored the key optical properties of this system and how these properties relate to the applied magnetic field. We have observed general aspects of polarized light obtained by transmission in a Ferrocell using polariscopes and analyzing the resulting Jones vector, such as the formation and rotation of dark bands known as isogyres. We suggest that in a thin film of ferrofluid as in a Ferrocell, two effects occur. The primary effect is dichroism, which is more sensitive to the component of the magnetic field in the direction parallel to the film plane. The secondary effect is the birefring...

Condensed Matter, 2021

We studied the effects of image formation in a device known as Ferrocell, which consists of a thi... more We studied the effects of image formation in a device known as Ferrocell, which consists of a thin film of a ferrofluid solution between two glass plates subjected to an external magnetic field in the presence of a light source. Following suggestions found in the literature, we compared the Ferrocell light scattering for some magnetic field configurations with the conical scattering of light by thin structures found in foams known as Plateau borders, and we discuss this type of scattering with the concept of diffracted rays from the Geometrical Theory of Diffraction. For certain magnetic field configurations, a Ferrocell with a point light source creates images of circles, parabolas, and hyperboles. We interpret the Ferrocell images as analogous to a Möbius transformation by inversion of the magnetic field. The formation of circles through this transformation is known as horocycles, which can be observed directly in the Ferrocell plane.

The dynamics of bubble, drop, and foam formation can present chaotic behavior. Under certain cond... more The dynamics of bubble, drop, and foam formation can present chaotic behavior. Under certain conditions these systems present routes to chaos such as period doubling, period adding, or intermittency. In addition to these aspects, some interesting emergent types of fragile objects can be observed, such as antibubbles.

Frontiers in Optics / Laser Science, 2020

We present results of the laser scattering in some structures of foams known as Plateau borders. ... more We present results of the laser scattering in some structures of foams known as Plateau borders. The light patterns are Parlaseric Circle with Laser Dogs and Horus Eye. Parlaseric Circle is due to conical diffraction.

11th Chaotic Modeling and Simulation International Conference, 2019

We have developed a magneto-optical system which simulates the stability of fixed points and the ... more We have developed a magneto-optical system which simulates the stability of fixed points and the trajectories of orbits present in dynamical systems. The question of stability is significant because a real-world system is constantly subject to small perturbations, and these orbits can be observed with a Ferrocell, a device using ferrofluid, which is a superparamagnetic fluid obtained with a kind of colloid containing surfactant coated nanometer ferromagnetic particles dispersed in a carrier liquid, and this device can be used in applications of optical effects. Our magneto-optical system is based in a Hele-Shaw cell containing ferrofluid, illuminated with an external light source, such as LED. By injecting a light propagating along the in-plane direction of the liquid film, the orbits can be observed, in a way that we can bend the light. The trajectories of the orbits are obtained by the diffracted light, which consists of light patterns, and these light patterns are related to Faraday effect, linear dichroism, and linear birefringence. The diffraction pattern is different from that produced by a wire because there are no fringes in these light patterns, and the absence of well-defined spacing between the fringes indicates the existence of multiple diffraction. Under certain circumstances, these light patterns can have the same properties of the force lines of magnetic fields. The main idea of this work is to propose a device applied to non-linear systems, based on magneto-photonics. We present the patterns obtained for different magnetic fields simulating dynamical systems.

Frontiers in Optics + Laser Science APS/DLS, 2019

We have investigated the light patterns in a thin film of ferrofluid subjected to a magnetic fiel... more We have investigated the light patterns in a thin film of ferrofluid subjected to a magnetic field, in a device known as Ferrolens. We observed magnetic contours and light polarization effects.

Frontiers in Optics + Laser Science APS/DLS, 2019

We developed some optical elements to observe some peculiar laser patterns. We obtained the Spira... more We developed some optical elements to observe some peculiar laser patterns. We obtained the Spiralbow and the involute of a circle. We designed a Hyperbolic Prism and obtained the pattern know as the Parlaseric Circle.