Advanced photonic materials for exotic light control

When?

Thursday 14 June 2012, 13:00 to 14:00

Where?

ATI seminar room, 02ATI02

Open to:

Staff, Students

Speaker:

Stavroula Foteinopoulou, School of Physics, University of Exeter

Current and emerging photonics technologies call for controlled light manipulation over a wide spectral range, from THz to visible/UV frequencies. Thus, modern photonics urge us to go beyond the possibilities of natural bulk materials. Micro/nano-structured materials can be engineered to exhibit exotic electromagnetic (EM) responses determined by both the composition and the spatial arrangement of their macroscopic elementary building blocks. These manmade "meta-atoms" offer limitless possibilities for unconventional photonic responses restricted only by our imagination and state-of-the-art fabrication methods.

Despite intensive efforts to conceive and construct metamaterials in the last decade, there is still substantial lack of methods to characterize and assert an effective-metamaterial signature. In this talk, I propose reliable criteria manifesting a fingerprint of bulk metamaterial behavior for two-dimensional composites. I will present paradigm metamaterials, -- constructed with the aid of such criteria--, that can function as THz optical set-up components, where traditional visible optics fails.

Moreover, outside the effective-metamaterial regime, I will present a metallic nano-hole non-resonant platform, which is demonstrating unprecedented broadband near-field enhancement with high transparency. Finally, I propose a semiconductor-based photonic crystal paradigm with near-perfect mid-IR absorption within the phonon-polariton gap of the bulk constituents and analyze the underpinning key factors that lead to absorption optimisation.