Reporter: Prof. Dang yuan Lei

Time: 2024-07-11 15:00-16:00

Place: The Large Conference Room on the second floor, B4

Abstract

Generally speaking, macroscopic structure symmetrical plasmon optical nanocavities, such as a pair of metal nanospheres of the same size and material, only support optical bright mode excitation that is allowed by symmetry. Breaking the symmetry of the optical cavity structure introduces bright mode and dark mode hybridization, which can produce new plasmon resonance modes, such as Fano resonance and continuous domain bound states. This report will explore three optical physics phenomena that have been overlooked for a long time in the symmetrical breakdown plasmon nanocavity, including (1) photo-induced electromagnetic asymmetric enhancement of second harmonic generation of precious metal surfaces (SHG). This new physical mechanism increases the efficiency of SHG conversion by three orders of magnitude compared with traditional enhancement strategies (Nature Communications 2021, 12, 4326; Nanophotonics 2024, in press); (2) second-order nonlinear optical response induced by photon-assisted quantum tunneling in plasmon molecules nanojunctions (Nano Letters 2023, 23(12), 5851-5858), expected to be a brand new paradigm of all-optical single-molecular quantum sensing; (3) Optical magnetism induced by plasmons in asymmetric nanocavity with nanoparticle dimer-mirror coupling and its theoretical analysis as a new second-order optical nonlinear source (Laser & Photonics Reviews 2020, 14(9), 200068)

Biography

Dang yuan Lei , professor at City University of Hong Kong, deputy director of the Centre for Functional Photonics Research, a visiting professor at Imperial College London, an academician of the Hong Kong Youth Sciences, and a recipient of the National Outstanding Youth Science Foundation (Hong Kong and Macao). He has been engaged in ultrafast nonlinear spectroscopy of nanoscale quantum photonics and low-dimensional quantum optical materials for ultrafast nonlinear spectroscopy, paying special attention to the physical mechanism of nanocavity-enhanced light and matter interactions and device applications in energy conversion, optoelectronic devices and biophotonics. To date, a total of 230 academic papers have been published, with a total of nearly 13,100 citations, and h-index is 65. Its research on multi-photon pumping and ultra-low threshold quantum dot lasers was selected as the 50 most read articles in the physics field in 2020 by Nature Communications magazine; the intelligent radiation refrigeration coating he invented with his collaborators was featured as an editor's selection by Science magazine, and its application in green buildings and thermal management of electronic devices won two gold medals in the Geneva International Invention Exhibition.