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Publications

Publications by Nuno Azevedo Silva

2017

Solving the multi-level Maxwell-Bloch equations using GPGPU computing for the simulation of nonlinear optics in atomic gases

Authors
Costa, JC; Gomes, M; Alves, RA; Silva, NA; Guerreiro, A;

Publication
THIRD INTERNATIONAL CONFERENCE ON APPLICATIONS OF OPTICS AND PHOTONICS

Abstract
We present a numerical implementation of a solver for the Maxwell-Bloch equations to calculate the propagation of a light pulse in a nonlinear medium composed of an atomic gas in one, two and three dimensional systems. This implementation solves the wave equation of light using a finite difference method in the time domain scheme, while the Bloch equations for the atomic population in each point of the simulation domain are integrated using splitting methods. We present numerical simulations of atomic-gas systems and performance benchmarks.

2017

Space- time refraction of light in time dependent media: the analogue within the analogue

Authors
Guerreiro, A; Mendonca, JT; Costa, JC; Gomes, M; Silva, NA;

Publication
THIRD INTERNATIONAL CONFERENCE ON APPLICATIONS OF OPTICS AND PHOTONICS

Abstract
The problem of electromagnetic wave propagation in time varying media is very old, but in recent years it has been revisited at a more fundamental level leading to the introduction of several new concepts, such as Time Refraction. These concepts explore the symmetries between space and time and can be transposed to different fields by establishing powerful analogies between effects in Electrodynamics, Optics and problems in Quantum Cosmology and in what is sometimes called Analogue Gravity. We examine the alteration of the ordinary (spatial) Fresnel laws of refraction at the interface between two media when the optical properties of one of the media varies in time.

2017

The Analogue Quantum Mechanical of Plasmonic Atoms

Authors
Alves, RA; Silva, NA; Costa, JC; Gomes, M; Guerreiro, A;

Publication
THIRD INTERNATIONAL CONFERENCE ON APPLICATIONS OF OPTICS AND PHOTONICS

Abstract
Localized plasmons in metallic nanostructures present strong analogies with Quantum Mechanical problems of particles trapped in potential wells. In this paper we take this analogy further using the Madelung Formalism of Quantum Mechanics to express the fluid equations describing the charge density of the conduction electrons and corresponding interaction with light in terms of an effective generalized Non-linear Schrodinger equations. Within this context, it is possible to develop the analogy of a plasmonic atom and molecule that exhibits Rabi oscillations, Stark effect, among other Quantum Mechanical effects.

2017

Physical ray-tracing method for anisotropic optical media in GPGPU

Authors
Guerreiro, A; Costa, JC; Gomes, M; Alves, RA; Silva, NA;

Publication
THIRD INTERNATIONAL CONFERENCE ON APPLICATIONS OF OPTICS AND PHOTONICS

Abstract
In this paper we discuss the development of a fast ray-tracing solver for complex anisotropic uniaxial optical media based on heterogeneous supercomputing in GPGPU using PyOpenCl. This solver simulates both the propagation of ordinary and extraordinary rays, while taking into account the polarization rotation introduced by position dependent modulations of the optical axis of the medium. We demonstrate the application of this solver by simulating the generation of polarization caustics in random uniaxial optical media.

2017

Development of a Quantum Particle in Cell algorithm in GPU for solving Maxwell-Bloch equations

Authors
Gomes, M; Costa, JC; Alves, RA; Silva, NA; Guerreiro, A;

Publication
THIRD INTERNATIONAL CONFERENCE ON APPLICATIONS OF OPTICS AND PHOTONICS

Abstract
In this paper we report on the development of a numerical solver for Vlasov equations based on heterogeneous supercomputing using GPGPUs. The solver adapts techniques from many-body simulation, namely the particlein-cell approach, to describe the interaction between the electromagnetic field and atomic gas whose internal state can be described by the multilevel Bloch equations. We also present the benchmark and performance analysis of the code. We investigate the interaction between two coherent light beams, as a case of study to demonstrate the validation of the code.

2017

Fast physical ray-tracing method for gravitational lensing using heterogeneous supercomputing in GPGPU

Authors
Costa, JC; Gomes, M; Alves, RA; Silva, NA; Guerreiro, A;

Publication
THIRD INTERNATIONAL CONFERENCE ON APPLICATIONS OF OPTICS AND PHOTONICS

Abstract
In this work we address the development of a fast solver of the ray-tracing equations based on heterogeneous supercomputing using PyOpenCL. We apply this solver to the study of gravitational lensing and light propagation in optical systems.

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