摘要

In this talk I will review recent results pertaining to nonlinear and quantum optical effects in bulk and nanostructured two-dimensional (2D) materials. I will start with the introduction of some theoretical concepts and numerical methods widely used in the study of optical properties of periodic structures and photonic devices, such as metamaterials, diffractive optical elements, and plasmonic structures. In particular, I will explain how the mathematical formulation of these methods can be extended to incorporate quadratic and cubic nonlinear optical effects, a key improvement that makes these methods powerful tools for the exploration of nonlinear optical effects at the nanoscale. In the second part of the talk I will illustrate how these methods can be used to design nonlinear photonic devices with new functionalities and explore new, intriguing nonlinear optical effects at deep subwavelength scale. To this end, I will demonstrate enhanced nonlinear optical interactions in periodically patterned photonic nanostructures via resonant excitation of phase-matched nonlinear waveguide modes, enhanced nonlinearity of nanostructures containing graphene and other 2D nanomaterials (MoS2, WSe2), tunable Fano resonances for increasing the nonlinear efficiency of hybrid 2D-3D photonic heteromaterials, and nonlinear interaction of topologically-protected edge modes of graphene nanostructures and 2D photonic crystals, including second-harmonic generation, third-harmonic generation, and four-wave mixing. Quantum plasmonic effects in graphene nanoflakes will be discussed as well. More specifically, I will focus on the differences between the physical properties of classical plasmons of relatively large graphene nanostructures and those of quantum plasmons of molecular-scale graphene nanoflakes. It will be revealed that one of the key differences between the classical and quantum plasmons is reflected by the scaling laws governing the size dependence of the plasmon energy.

报告人简介

Nicolae C. Panoiu received the B.Sc. and M.Sc. degrees in physics from the University of Bucharest, Bucharest, Romania, in 1990 and 1992, respectively, and the Ph.D. degree in physics from New York University (NYU) in 2001. From 1992 to 1995 he was a Staff Member at the Horia Hulubei National Institute of Physics and Nuclear Engineering, Department of Theoretical Physics in Bucharest, Romania. After graduating from NYU, he was a Postdoctoral Fellow and then Research Scientist in the Department of Applied Physics and Applied Mathematics, Columbia University, USA. He is currently Professor of Nanophotonics with the Department of Electronic and Electrical Engineering, University College London, London, U.K. His research interests include silicon photonics, optical properties of photonic nanostructures and metamaterials, and computational modeling of electromagnetic structures. He is author of more than 180 journal papers and 190 conference talks.