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Mário Silveirinha awarded £350,000 research grant to ‘break’ time-reversal symmetry with mechanical motion

on 01-01-2019

... Professor Mário Silveirinha, from the University of Lisbon and researcher at IT is the winner of the £350,000 IET A. F. Harvey Engineering Research Prize. He was chosen from high-calibre candidates from across the world as a result of his new approach and vision of how time reversal symmetry can be broken with ‘mechanical motion’, such as by injecting a drift electric current into a material.

The funding will support a further five years of work with the aim of showing how such solutions may enable the one-way propagation of microwave and terahertz waves totally immune to the undesired effects of back-scattering by obstacles, imperfections, and other deformations of the propagation path.

Professor Silveirinha, said: “I am extremely honoured to receive the IET A. F. Harvey Engineering Research Prize. It is rather inspiring that Dr. Arthur F. Harvey was himself one of the pioneers of nonreciprocal microwave devices, and I am thrilled that I will be able to build my own research on nonreciprocal and topological electromagnetics with the generous support of his Prize and contribute with innovative solutions for future technologies”.

Sir John O’Reilly, Chair of the IET’s Selection Committee for the Prize, said: “Prof. Mário G. Silveirinha is awarded the A F Harvey Research Prize in recognition of his outstanding research achievements and as a pioneer in the field of near-zero index materials and photonics. This is a fundamental research area that will have important implications for applications such as mobile radio, radar, and optical fibre communication networks in the future.”

The IET’s A F Harvey Research Prize, worth £350,000, is named after Dr. A. F. Harvey who bequeathed a generous sum of money to the IET for a trust fund to be set up in his name for the furtherance of scientific research into the fields of medical, microwave, laser or radar engineering.

Prof. Mário Silveirinha will present a prize lecture on his research at IET London: Savoy Place on 18 March 2019.

Optical platforms for monitoring the quality of liquids

on 20-12-2018

... Water distributers and beverage industries have the concern to guarantee the desirable quality parameters of their products during all their grid systems and production lines. The activity coordinated by Rogério Nogueira and Lúcia Bilro (both from IT in Aveiro) aims to develop low-cost, smart optical platforms for on-line and real-time measurement of liquid properties and/or chemical and biological constituents. These platforms are based in optical fiber technology and framed as a natural development after the conclusion of the IT internal project “sWAT”.

sWAT project provided the base on-line cloud platform which was developed to store, treat and display data from sensors placed in the field, such as water suppling tanks. Previously developed sensors for turbidity, color and refractive index sensing can be wireless connected to this platform. The first developed prototype was the turbidity sensor used to measure the quantity of suspended solids directly from a suppling point of water installed in Segadães, Águeda. It uses the transmission and scattering of infrared light guided through plastic optical fibers (POF) that are in contact with the water.

The evolution of this sensor led to the development of a color sensor prototype where other light wavelengths were added to give color sensing capability. With this prototype, machine learning and data fusion data treatment algorithms were developed to optimize the selectivity and detection limits of the sensor.

Finally, two low-cost refractive index (RI) sensors were also designed and developed. The first one, uses a hybrid POF to prism structure and is intended to monitor the quality of water with real-time high precision measurements. By determining the position of light that is totally reflected in a prism-liquid interface, a value for RI can be obtained. The direct measurement of RI can give us an indirect value of any variation in the quality of a liquid. A pilot case study will be conducted soon. The alternative approach to this sensor uses a POF side polished that will be in contact with the liquid to be measured. The principle of operation is based on the variation of the transmitted light through the side-polished section of the fiber due to RI variations of the liquid being monitored. Future work will use this device as a base where polymeric layers are deposited over, which are sensitive to chemical and biological constituents. This work will be further developed in the recently initiated AQUATICsens FCT project.