metamaterials

Light management in non-Hermitian media

Dr. Waqas Ahmed, Electrical Engineering, King Abdullah University of Science and Technology

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KAUST

Structured media provide the momentum compensation for the scattering of waves. It is well-known that nano-scale modulations of the refractive index may lead to a temporal and spatial control over light propagation. Yet, also engineering the gain and loss profile uncovers analogous shaping effects. However, only the interplay between both the refractive index and gain and loss modulations introduces unidirectionality in light management. Thus, non-Hermitian optics has become one of the most fertile grounds in optics. A generalized Hilbert transform allows tailoring the two quadratures of the complex permittivity to design periodic or disordered non-Hermitian media, holding either global or local unidirectionality following arbitrary vector fields to tailor the flow of light. The method allows restricting the permittivity within realistic values rendering it suitable for applications.

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Ying Wu

Professor Wu works on theoretical modeling and numerical simulations of classical wave propagation in complex media, including metamaterials, metasurfaces, topological materials and random systems. She is recognized by effective medium theory, perturbation theory for periodic structures with resonances.