Graphene-based devices for Terahertz photonics

by Prof. Alessandro Tredicucci (Università di Pisa)

Tuesday 28 Oct 2014, 08:00 → 09:30 Europe/Rome

131 (INFN edificio C)

Graphene, a single-layer of carbon atoms arranged in a two-dimensional honeycomb lattice is nowadays attracting considerable attention for a variety of photonic applications, including fast photodetectors, transparent electrodes in displays and photovoltaic modules, and saturable absorbers. Owing to its high carrier mobility, gapless spectrum, and frequency-independent absorption coefficient, it has been precognized as a very promising element for the development of detectors and modulators operating in the Terahertz (THz) region of the electromagnetic spectrum (wavelengths in the hundred μm range), which is still severely lacking in terms of solid-state devices. Here I will illustrate the realization of THz detectors based on antenna-coupled single-layer and bilayer graphene field-effect transistors (FETs), and discuss the development and applications of electrically switchable metamaterial devices. Prospects for the use of graphene in a new generation of THz sources, both directly and as saturable absorber for laser mode-locking, will be analyzed. Finally, coherent perfect absorption processes and possible applications will be presented.