Research Lines

Integrated Optics:

In this research line, we focus our work on the so-called "Silicon Photonics", or more specifically "Silicon Nanophotonics", which besides being an emerging field of research and technology, it's a reality of innovation present in new products. Our research includes advances in nano-silicon devices or silicon nitride, such as: waveguides, optical resonators and couplers based on Bragg grids. Within this line, we highlight the computational simulations in:

Optical Transform and Invisibility:

We seek development on new strategies of mapping in transformal optics that result in a transformation whose resulting optical medium is isotropic or has low anisotropy. We study and investigate different coordinate transformations for planar waveguides, whose goals are to modify the trajectory of the eletromagnetic wave and develop devices such as waveguides, isotropic polarization dividers or even invisibility mantles.

Design and Modeling of Silicon Nano Grids:

The optical coupling of nano-photonic devices can be made via Bragg Grids. The computacional modeling of these grids is fundamental to increase the coupling efficiency between the nanoscale guides and the conventional optical fibers of a telecommunication network. Thus, in this research line, we simulate new structural arrangements of guides, reflective layers and different doping in order to increase the coupling efficiency.


Photonic Crystal Optical Fibers:

In this research line, we focus on the investigation of this new class of optical fibers, based on the concept of photonic crystals, called Photonic Crystal Fiber (PCF) or Microstructured Optical Fiber (MOF). By using materials with different refraction indexes periodically structured, its particular geometry allows a high project flexibility. Therefore, it's possible to adjust, as required, the dispersion properties, effective area, confinement losses, and so on. It makes these fibers especially useful for applications in optical communications. Within this research line, we highlight the computational simulation in:

Optical Sensing:

Chromatic dispersion is one of the main limiting factors in current fiber-optic data transmission systems. So, the development of optical devices capable of compensating this unwanted effect is fundamental. The photonic crystal optical fibers used for dispersion compesation, due to their geometry, stand out for their high malleability in the design of dispersion curves. In this research line, we seek to adequately manipulate the geometric and structural parameters of PCFs to modify, according to necessity and palation, the fibers chromatic dispersion values.

Design and Modeling of Silicon Nano Grids:

The optical coupling of nano-photonic devices can be made via Bragg Grids. The computacional modeling of these grids is fundamental to increase the coupling efficiency between the nanoscale guides and the conventional optical fibers of a telecommunication network. Thus, in this research line, we simulate new structural arrangements of guides, reflective layers and different doping in order to increase the coupling efficiency.


Antennas and Propagation:

In this research line, the focus is on the theoretical and practical investigation of new antennas and antenna arrangements capable of performing high gain with maximum efficiency, self-tuning and also being optically controlled. Then, we can develop antennas operating in broadband and/or operating in different frequencies bands. Within this research line, we highlight the simulations and experiments in:

Wireless power transfer:

It's a known fact that the efficiency of wireless energy transmission is directly related to the distance between the transmitting and receiving device. Plus, the energy transfer is extremely sensitive to the operating resonance frequency of the system. Thus, we seek to develop analytical, numerical, and experimentally self-tuning, wireless energy transfer devices capable of operating at the point of maximum efficiency.

Lens-assisted wide-band antennas:

The initial proposition is to investigate, through numerical simulations and practical experiments, new geometric arrangements of wide-band antennas assisted by dielectric lenses. So, we seek the development of new solutions for the existing issues in wireless communication systems, designing high gain antennas, and yet operating across a broad spectrum range. These new antennas will be designed along with a dielectric lens to operate in the UHF range (0.3GHz), up to the beginning of the TeraHertz range (300GHz).

Optically controlled antennas:

In this application, it's sought to develop antennas with reconfigurable and optically controlled standards, operating in the millimetric wave frequency range. Silicon switches are used to control optical reconfiguration by modifying the frequency response and antenna radiation pattern. Therefore, we design and develop new antenna structures and arrangements, controlled optically by the optical switch, which responds extremely fast. This project is developed in partnership with the WOCA team from INATEL


NEW Redes de TelecomunicaƧƵes

The fast growth of information and communication technologies has led to a considerable increase in energy consumption. Thus, the reduction of energy costs in telecommunications networks has become one of the issues to be solved. In this way, we have developed techniques and algorithms capable of reducing these energy expenditures in telecom networks, specifically in the so-called Elastic Optical Networks (EON). Therefore, in this research line, we seek to develop smart techniques, capable of improving energy efficiency in optical networks.


NEW Dispositivos em Terahertz

Modeling of the electro-optical effect in LID devices, for applications in THz range modulators. The objective of this project is to develop an electro-optical modulator by applying the technique of confinement of the electromagnetic wave in lower refraction index environment, through the discontinuity in the interface between the environments, as what happens in devices known as LIDs. For this, the electro-optical effect is investigated in anisotropic crystals that belong to this category of optical devices.