Natural transparent materials like glass or crystal always induce a certain amount of reflection due to impedance mismatch, except for selected polarization and a single incident angle denoted as the Brewster's angle. Artificial electromagnetic materials like metamaterials or photonic crystals provide the possibility to break this limit and realize ultra-transparency. By using photonic media with spatial dispersions, which are usually viewed upon as a nuisance rather than an advantage, total transparency for a wide range of and even all incident angles can be surprisingly achieved, i.e. ultra-transparent materials. Such an ultra-transparency effect is proved numerically and experimentally by a photonic crystal with a shifted elliptical dispersion, which also supports formation of ideal virtual images without aberrations. The speaker’s work provides a theory for constructing ultra-transparent spatially dispersive media, and proposes a photonic crystal approach to realize such media, opening rich possibilities in novel optical designs such as wide-angle super-polarizer and transformation optics devices.
About the speaker
Prof Yun Lai obtained his Bachelor's degree in Nanjing University in 1999 and his PhD degree in HKUST in 2005. He was a Research Associate in HKUST after graduation and became a professor in Soochow University in 2011. He is currently a Professor in the College of Physics, Optoelectronics, and Energy in Soochow University. Prof Lai has published more than 30 Science papers including Nature Materials and Physical Review Letters. The total citation of his paper exceeds 1000.
The seminar is free and open to all. Seating is on a first-come, first-served basis.
