Dr. Nuno Azevedo Silva Profile

Dr. Nuno Azevedo Silva

Assistant Researcher at INESC TEC

SPIE Involvement:

Author

Publications (32)

Proceedings Article | 18 June 2024 Poster + Paper

Enabling optical extreme learning machines with nonlinear optics

Nuno Silva, Vicente Rocha, Tiago Ferreira

Proceedings Volume 13017, 1301716 (2024) https://doi.org/10.1117/12.3022338

KEYWORDS: Nonlinear optics, Extreme learning machines, Sensors, Optical computing, Beam propagation method, Computer architecture, Wavefronts

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Proceedings Article | 18 June 2024 Poster + Paper

All-optical output layer in photonic extreme learning machines

Vicente Rocha, Tiago Ferreira, Nuno Silva

Proceedings Volume 13017, 1301714 (2024) https://doi.org/10.1117/12.3021888

KEYWORDS: Education and training, Spatial light modulators, Mathematical modeling, Extreme learning machines, Amplitude modulation, Optical computing, Systems modeling, Digital micromirror devices

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Proceedings Article | 18 June 2024 Poster + Paper

Augmented reality for spectral imaging applications

Rafael Cavaco, Tomás Lopes, Pedro A. Jorge, Nuno Silva

Proceedings Volume 12996, 129960X (2024) https://doi.org/10.1117/12.3022157

KEYWORDS: Augmented reality, Imaging spectroscopy, 3D modeling, Visualization, Statistical modeling, Autoregressive models, 3D image processing, Human-machine interfaces, Data modeling, Alignment modeling

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Proceedings Article | 10 June 2024 Presentation + Paper

Probing molecular affinity with optical tweezers

Joana Teixeira, José Ribeiro, Pedro A. Jorge, Nuno Silva

Proceedings Volume 12991, 1299105 (2024) https://doi.org/10.1117/12.3022142

KEYWORDS: Particles, Optical tweezers, Proteins, Antibodies, Random forests, Molecular interactions, Data modeling

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Proceedings Article | 18 April 2021 Poster + Presentation + Paper

Superfluid effects in defocusing nematic liquid crystals

Tiago Ferreira, Nuno Silva, Ariel Guerreiro

Proceedings Volume 11770, 117701U (2021) https://doi.org/10.1117/12.2592311

KEYWORDS: Liquid crystals, Control systems, Complex systems, Beam propagation method, Turbulence, Quantum optics, Photons, Numerical analysis, Nonlinear optical materials, Diffraction

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The last years saw the emergence of nonlinear optical materials, with local and nonlocal nonlinearities, as experimentally accessible systems to implement optical analogues of quantum fluids. In these systems, a light beam propagating in the nonlinear medium can be interpreted as a fluid, where the diffraction in the transverse plane to the propagation gives the effective mass of the fluid and the medium nonlinearity mediates the required interactions between the photons. This fluid interpretation and its application have been extensively studied, from the creation of superfluid-like flows and the study of phenomena associated with this effect to the implementation of gravity analogues. Furthermore, many optical materials have been considered, with a special interest in the ones that offer tunable mechanisms that allow to easily control the system properties to better explore and emulate the different phenomena. Recently, nematic liquid crystals have been proposed as an interesting tunable material capable of supporting superfluids of light. These systems have a nonlocal character and offer external mechanisms that can be used to tailor the nonlinearity to better emulate the desired analogue system. Indeed, through the application of an external electric field perpendicular to the direction of propagation, is it possible to control the nonlocal length of the nonlinearity. This mechanism offers interesting opportunities in the present context. In this work, through numerical methods based on GPGPU supercomputing, we explore the possibility of observing superfluid effects in defocusing nematic liquid crystals. In particular, we explore the possibility of observing the drag force cancelation and the emission of quantized vortices, which are two manifestations of a superfluid flow. Furthermore, we also discuss the possibility of using these systems for creating an analogue of quantum turbulence with these materials. These studies constitute a stepping-stone towards the implementation of gravity analogues with nematic liquid crystals.

Proceedings Article | 18 April 2021 Presentation + Paper

Analogue cosmology: using techniques from nonlinear optics to study modified theories of gravity with non-minimal coupling between curvature and matter

Tiago Ferreira, João Novo, O. Bertolami, Nuno Silva, Ariel Guerreiro

Proceedings Volume 11770, 1177018 (2021) https://doi.org/10.1117/12.2592316

KEYWORDS: Systems modeling, Mathematical modeling, Nonlinear optics, Complex systems, Numerical analysis, Geometrical optics, General relativity, Nonlinear optical materials, Fluid dynamics

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The Theory of General Relativity is currently the most accepted model to describe gravity, and although many experiments and observations continue to validate it, recent astrophysical and cosmological observations require to include new forms of matter and energy (dark matter and dark energy), to be consistent. Modified theories of gravity with non-minimal coupling between curvature and matter are extensions of the Theory of General Relativity and have been proposed to address these shortcomings. Interestingly, matter at large scales behaves as a fluid and under certain approximations, the field equations can be approximated to a generalized Schr¨odingerNewton system of equations. This model is largely found in the nonlinear optical systems, in particular to describe light propagating in nonlinear and nonlocal optical materials and also as a base model for the development of many optical analogues. Due to this, there are a wide variety of numerical methods developed to tackle this type of mathematical models, and that can be used to study these alternative gravity models. In this work, we explore the application of these numerical techniques based on GPGPU supercomputing, initially developed to study light propagating in nonlinear optical systems, to explore a particular non-minimal coupled gravity model. This model, in the nonrelativistic limit, modifies the hydrodynamic equations with the introduction of an attractive Yukawa potential and a repulsive one proportional to the matter density. We used the Schr¨odinger-Newton formalism to numerically study this model and, through the imaginary-time propagation method, we found stationary solutions that were sustained by the repulsive potential introduced by the non-minimal coupled model, even in the absence of a pressure term. We developed an analytical study in the Thomas-Fermi approximation and compared the predictions with numerical solutions. Finally, we explored how this gravity model may be emulated in the laboratory as an optical analogue.

Proceedings Article | 18 April 2021 Poster + Presentation + Paper

Exploring quantum-like turbulence with a two-component paraxial fluid of light

Nuno Azevedo Silva, Tiago Ferreira, Vicente Rocha, Ariel Guerreiro

Proceedings Volume 11770, 117701V (2021) https://doi.org/10.1117/12.2592334

KEYWORDS: Turbulence, Nonlinear optics, Fluid dynamics, Quantum physics, Radio propagation, Polarization, Electromagnetism, Complex systems, Beam propagation method

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Proceedings Article | 18 April 2021 Presentation + Paper

Reservoir computing with optical solitons

Nuno Azevedo Silva, Tiago Ferreira, Duarte Silva, Ariel Guerreiro

Proceedings Volume 11770, 1177013 (2021) https://doi.org/10.1117/12.2592329

KEYWORDS: Optical solitons, Solitons, Data processing, Complex systems, Ultrafast phenomena, Signal processing, Optical computing, Nonlinear dynamics, Computing systems, Computer architecture

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Proceedings Article | 3 October 2019 Paper

A hardware-independent solution for high-performance simulations of the Maxwell-Bloch system

Nuno Silva, T. Ferreira, A. Guerreiro

Proceedings Volume 11207, 1120718 (2019) https://doi.org/10.1117/12.2527336

KEYWORDS: Computer simulations, Parallel computing, Photonics, Nonlinear optics, Quantum optics, Computational physics

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Proceedings Article | 3 October 2019 Paper

Developing tunable optical analogues using nematic liquid crystals

Tiago Ferreira, Nuno Silva, Ariel Guerreiro

Proceedings Volume 11207, 1120709 (2019) https://doi.org/10.1117/12.2526408

KEYWORDS: Liquid crystals, Geometrical optics, Systems modeling, Liquids, Rotons, Molecules, Numerical simulations, Nonlinear optics, Complex systems, Helium

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Proceedings Article | 3 October 2019 Paper

Fluids of light in atomic systems: from superfluidity to quantum simulations

Nuno Silva, T. Ferreira, A. Guerreiro

Proceedings Volume 11207, 1120717 (2019) https://doi.org/10.1117/12.2527321

KEYWORDS: Quantum physics, Beam propagation method, Quantum optics

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Proceedings Article | 3 October 2019 Paper

Hilight: a new simulation platform for advanced photonics

A. Guerreiro, Nuno Silva, João Costa, Miguel Gomes, Ruben Alves, Tiago Ferreira, Inês Madureira, André Almeida, André A. Pereira

Proceedings Volume 11207, 112071U (2019) https://doi.org/10.1117/12.2527441

KEYWORDS: Electromagnetism, Chemical species, Systems modeling, Computer simulations, Radio propagation, Nonlinear optics, Gases, Particles, Beam propagation method, Photonics

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Proceedings Article | 3 October 2019 Paper

Exploring dissipative optical solitons controlling gain and loss in atomic systems

Nuno Silva, T. Ferreira, A. Guerreiro

Proceedings Volume 11207, 1120719 (2019) https://doi.org/10.1117/12.2527338

KEYWORDS: Solitons, Optical solitons, Polarization, Quantum optics, Nonlinear optics

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Proceedings Article | 3 October 2019 Paper

Quantum fluid equations for atomic gases

A. Guerreiro, T. Ferreira, Nuno Silva

Proceedings Volume 11207, 112071T (2019) https://doi.org/10.1117/12.2527440

KEYWORDS: Chemical species, Doppler effect, Gases, Particles, Systems modeling, Motion models, Light-matter interactions, Clouds, Fluid dynamics, Quantum physics

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Proceedings Article | 3 October 2019 Paper

Functional metamaterials for optical sensing of hydrogen

A. Guerreiro, Arlete Apolinario, Armandina Lopes, Aurelio Hierro-Rodriguez, Gerardo Aguilar, Jose Manuel Baptista, Nuno Silva, Orlando Frazão, Paula Virginia Quiterio, Pedro Jorge, Pedro Rodrigues, Suellen Silveira Moraes, Susana Silva, Tiago Ferreira, Jose Luis Santos, João Pedro Araujo

Proceedings Volume 11207, 1120724 (2019) https://doi.org/10.1117/12.2527672

KEYWORDS: Palladium, Metamaterials, Hydrogen, Optical properties, Refractive index, Sensors, Nanowires, Optical sensing, Optical fibers, Dendrites

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Proceedings Article | 3 October 2019 Paper

Simulating N-body systems for alternative theories of gravity using solvers from nonlocal optics

Tiago Ferreira, Nuno Silva, O. Bertolami, C. Gomes, Ariel Guerreiro

Proceedings Volume 11207, 1120710 (2019) https://doi.org/10.1117/12.2527295

KEYWORDS: Systems modeling, General relativity, Geometrical optics, Computer simulations, Optical simulations, Complex systems, Beam propagation method, Liquid crystals, Paraxial approximations, Physics

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Proceedings Article | 3 October 2019 Paper

High-performance solver of the multidimensional generalized nonlinear Schrödinger equation with coupled fields

Tiago Ferreira, Nuno Silva, Ariel Guerreiro

Proceedings Volume 11207, 1120713 (2019) https://doi.org/10.1117/12.2527305

KEYWORDS: Systems modeling, Numerical analysis, Complex systems, Physics, Computing systems, Computer simulations, Light-matter interactions, Paraxial approximations, Nonlinear optics, Maxwell's equations

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Proceedings Article | 29 August 2017 Paper

Tunable light superfluids using quantum atomic optical systems

Nuno Silva, T. Ferrerira, J. Costa, M. Gomes, R. Alves, A. Guerreiro

Proceedings Volume 10358, 103580W (2017) https://doi.org/10.1117/12.2276241

KEYWORDS: Nonlinear optics, Paraxial approximations, Quantum physics, Optical properties

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