Center for Functional Nanomaterials Seminar

Scattering of light is a ubiquitous process, which has driven the curiosity of human minds for thousands of years, from ancient Greek philosophers to modern physicists. For a scattering process to occur, electromagnetic waves need to interact with matter. Wise tailoring of the light-matter interaction in structured materials lies at the center of today's experimental physics and technology, both in classical and quantum regimes. Hence, deep insight into the basics of scattering theory and understanding the peculiar features of electromagnetic scattering is necessary for the correct interpretation of experimental data, understanding of the underlying physics, and advanced applications. Recently, a broad spectrum of exceptional scattering phenomena attainable in suitably engineered structures has been predicted and demonstrated, including bound states in the continuum (BIC), exceptional points in PT-symmetrical non-Hermitian systems, coherent perfect absorption, virtual perfect absorption, and nontrivial lasing.

In this talk, I will discuss these unusual scattering phenomena with a focus on their application in quantum optics. I will provide a unified description of such exotic scattering phenomena and show that their origin can be traced to the fundamental properties of the underlying S-matrix. I will show that, on the other hand, these insights provide a powerful approach to tailor unusual scattering regimes for various advanced applications. Lastly, I will discuss future research directions in this fascinating and promising research area.