Publications by authors named "Mario F S Ferreira"

Optical sensors and sensing technologies are playing a more and more important role in our modern world. From micro-probes to large devices used in such diverse areas like medical diagnosis, defence, monitoring of industrial and environmental conditions, optics can be used in a variety of ways to achieve compact, low cost, stand-off sensing with extreme sensitivity and selectivity. Actually, the challenges to the design and functioning of an optical sensor for a particular application requires intimate knowledge of the optical, material, and environmental properties that can affect its performance.

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This joint feature issue of Optics Express and Applied Optics highlights contributions from authors who presented their latest research at the OSA Optical Sensors and Sensing Congress, held in San Jose, California, USA from 25-27 June 2019. The joint feature issue comprises 6 contributed papers, which expand upon their respective conference proceedings. The published papers introduced here cover a range of timely research topics in optics and photonics for active open-path sensing, radiometry, and adaptive optics and fiber devices.

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This joint feature issue of Optics Express and Applied Optics highlights contributions from authors who presented their latest research at the OSA Optical Sensors and Sensing Congress, held in San Jose, California, USA, from 25-27 June 2019. The joint feature issue comprises six contributed papers, which expand upon their respective conference proceedings. The published papers introduced here cover a range of timely research topics in optics and photonics for active open-path sensing, radiometry, and adaptive optics and fiber devices.

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Sensors are devices or systems able to detect, measure and convert magnitudes from any domain to an electrical one. Using light as a probe for optical sensing is one of the most efficient approaches for this purpose. The history of optical sensing using some methods based on absorbance, emissive and florescence properties date back to the 16th century.

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The impact of some higher-order effects (HOEs), namely, intrapulse Raman scattering, self-steepening, and third-order dispersion, on a chaotic pulsating soliton, solution of the quintic complex Ginzburg-Landau equation, is numerically investigated. We show that a proper combination of the three HOEs can control the pulse chaotic behavior and provide a fixed-shape solution. The region of existence of fixed-shape pulses is also presented for some range of the parameter values.

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The Raman gain based polarization pulling process in a copropagating scheme is investigated. We map the degree of polarization, the angle between the signal and pump output Stokes vectors, the mean signal gain and its standard deviation considering the entire Raman gain bandwidth. We show that, in the undepleted regime (signal input power ~ 1 μW), the degree of polarization is proportional to the pump power and changes with the signal wavelength, following the Raman gain shape.

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We investigate numerically the impact of some higher-order effects, namely, self-frequency shift, self-steepening, and third-order dispersion, on the erupting soliton solutions of the quintic complex Ginzburg-Landau equation. We consider particularly the impact of these higher-order effects in the spectral domain from which we can describe the pulse characteristics in the time domain. These effects can filter in different ways the spectral perturbations that contribute to pulse explosions.

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We numerically study the impact of self-frequency shift, self-steepening, and third-order dispersion on the erupting soliton solutions of the quintic complex Ginzburg-Landau equation. We find that the pulse explosions can be completely eliminated if these higher-order effects are properly conjugated two by two. In particular, we observe that positive third-order dispersion can compensate the self-frequency shift effect, whereas negative third-order dispersion can compensate the self-steepening effect.

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