Tuesday, September 4th, 2018, 14:00-15:30
Dr. Francesco Bonaccorso
IIT Central Research Lab, Genova
Solution processed 2D-materials for printed electronics
Graphene and other 2D crystals are emerging as promising materials to improve the performance of existing devices or enable new ones. A key requirement for flexible and printed electronics is the development of industrial-scale, reliable, inexpensive production processes, while providing a balance between ease of fabrication and final material quality. Solution-processing is a simple and cost-effective pathway to fabricate various 2D crystal-based (opto)electronic devices, presenting huge integration flexibility compared to conventional methods. Here, I will present an overview of graphene and other 2D crystals for flexible and printed (opto)electronic applications, starting from solution processing of the raw bulk materials, the fabrication of large area electrodes and their integration in the final devices.
Prof. Yang Hao
School of Electronic Engineering and Computer Science
Queen Mary, University of London
Nanoelectromagnetics at Microwave Frequencies and Beyond
Classic electromagnetics has witnessed novel developments in recent years due to the emergence of novel materials and concepts such as metamaterials and transformation optics. The theory of near-field electromagnetism has enabled us to explore structures in sub-wavelength scales and opens up new possibilities of imaging, sensing and characterisation of materials. In this talk, I will review our recent research activities related to nanoelectromagnetics applied to microwave frequencies and beyond. In particular, how novel electromagnetic modelling tools have been developed and applied for the development of device innovation.
Prof. Alexander I. Nosich
Institute of Radio-Physics and Electronics
National Academy of Sciences
Periodicity matters: ultrahigh-Q resonances on the grating modes of large arrays of subwavelength scatterers
This talk reviews the nature and history of the discovery of extremely high-quality natural modes existing on periodic arrays of many subwavelength scatterers. Thanks to these modes, infinite and large arrays can be viewed as specific periodically structured open resonators. These grating or lattice modes (GMs), like any other natural modes, give rise to the associated resonances in electromagnetic-wave scattering and absorption. Their complex wavelengths are always located very close to (but not exactly at) the well-known Rayleigh anomalies (RAs), determined only by the period and the phase shift between adjacent elements. This circumstance has long been a reason for their misinterpretation as RAs, especially in the measurements and simulations using low-resolution methods. On the frequency scans of the reflectance or transmittance, GM resonances usually develop as asymmetric Fano-shape double extrema. In the microwave range, GM resonances can spoil the performance of large phased-array antennas assembled on flat surfaces. In the optical range, GM resonances are found behind exotic phenomena such as “anomalous” transmission, reflection and absorption, giant Faraday, Kerr and Kerker effects, etc., and also behind the principle of operation of Distributed Feedback Lasers. If a grating is made of subwavelength-size noble metal elements, then collective GMs exist together with better-known localized surface-plasmon modes on individual particles. Their interplay can result in the effect of induced optical transparency. Thanks to high tunability and considerably higher Q-factors, the GM resonances can potentially replace the plasmon-mode resonances in the design of nanosensors, nanoantennas, and solar-cell nanoabsorbers.