Rafael E. P. de Oliveira

Position: Assistant Professor

Area de interest: Photonics

Email: repdeoliveira@mackenzie.br

Office: 406

Phone: + 55 11 2766-7384

Integrated Photonic Devices

 

Graphene and other nanomaterials are promising platforms for the development of the next generation of integrated photonic devices for high performance optical communications. The optical communication consists in the transmission of data using light as carrier, usually, through a waveguide, providing the transfer of data at high rates and the internet as we know it today. There is no guided transmission technology more efficient for high-speed data transmission and besides its use for long haul transmission through optical fibers, optical communications are also replacing metallic cables in short distances, as in Data Centers, once that it allows higher processing and transmission data rates. In a near future it is predicted that even the data transmission in chip interconnects will be carried by light, which allows higher transmission rates and also reduces the power consumption, once the optical transmission doesn’t dissipate heat as metal cables.


In that frame that this research group aims the development of photonic devices that manipulate light in more efficient ways for higher bit rates and with more integration with the nowadays systems. The photonic devices manipulate the light photons controlling determined light properties and are used for modulation and detection, inserting and detecting the data in the optical carrier, which are then processed and stored electronically. One of the objectives in the development of such devices in this group is the integration of the nanomaterials properties in manipulating light with fabrication techniques based on silicon. This integration with the silicon photonics will result in cheaper, more efficient and more compact devices with total integration with electronic chips, allowing a more efficient electro-optic communication interface and devices that can be used for light modulation and detection in either long haul systems, data centers and interconnect communications.


The MackGraphe has research groups that work from the graphene and other 2D materials syntheses up to their optical properties characterization, which identifies their potential for applications in photonic devices. From there, this research group performs analysis through numerical simulations to determine the device project and evaluate its performance in the system for which it is being designed. The next step is the device fabrication, experimental characterization and prototypes, which is performed in collaboration with the MackGraphe Photonic’s group and the photonics industry.

Microscopy image of a photonic chip composed of a silicon nitride waveguide covered with graphene. (a) Frontal waveguide view and (b) top view with the graphene highlighted.
Simulation of a photonic device showing the light distribution in a graphene covered waveguide.
Optical polarizing effect of a waveguide covered with a graphene layer (indicated by the white arrow) as function of the superstrate refractive index. Using the graphene is possible to obtain either Quasi-TE or Quasi-TM passing polarizers by adjusting the waveguide parameters.
Design of an integrated waveguide with graphene layers with metallic contacts for electro-optical modulation.

 Rafael was born in São Paulo in 1984. He received the degree of Electrical Engineer from Mackenzie University in 2006 and joined the Mackenzie University Photonics Group as undergraduate student in 2005. Within the same group, he obtained his Master’s degree in 2010 and his PhD in Electrical Engineering in 2014. His works in that period include the characterization of photonic crystal fibers, design and simulation of photonic devices, silicon photonics and nonlinear optics. During his PhD he spent one year at the Department of Optical Fibers in the ACREO Swedish ICT, developing a new technique for the fabrication of silica optical fibers containing gold nanoparticles for nonlinear optical applications. He joined the MackGraphe as Professor in 2015, focusing his work in the development of optical devices based on graphene and nanomaterials. His research interests include the project, simulation and fabrication of integrated optical and electro-optical devices for telecommunications, silicon photonics and nonlinear optical characterization of 2D materials.