| Time：1110216 (Wed.) 14:20~16:20
Speaker：Prof. 許良彥(Liang-Yan Hsu) 中央研究院原子與分子科學研究所/Institute of Atomic and Molecular Sciences, Academia Sinica Title：Quantum Electrodynamical Chemistry: Molecules Coupled with Vacuum Fluctuations of Electromagnetic Fields Abstract：In this talk, I will briefly introduce an emerging field “QED chemistry” and my latest development in this research direction. In the past two years, control of chemical processes by a vacuum electromagnetic field has received considerable attention because the entry of quantum electrodynamics into chemistry is a wholly new concept and a huge breakthrough in basic science. Quantum light can affect molecules in a variety of aspects, and I will focus on molecular fluorescence coupled with plasmon polaritons or cavity photons. In the framework of macroscopic quantum electrodynamics, I developed a unified theory of molecular fluorescence, which allows us to describe the dynamics of molecular fluorescence coupled to quantum light from weak to strong light-matter couplings (from Franck-Condon to polariton regimes) in a complicated dielectric environment. Based on this theory, we showed an interesting phenomenon called Franck-Condon-Rabi oscillation, and derived a parameter-free formula which can be used to estimate the exciton-polariton coupling for single molecules in a nanocavity. Our theory is in good agreement with the reported experimental results [Chikkaraddy et al., Nature 535, 127-130 (2016)]. In addition, we investigated the coherent-to-incoherent transition of molecular fluorescence of a chromophore above a silver surface (including bulk and thin-film systems) and explored the distance dependence of fluorescence rate enhancement. Moreover, in the presence of arbitrary inhomogeneous, dispersive, and absorbing media, we established a generalized theory of molecular emission power spectrum which can be expressed as the product of the lineshape function and electromagnetic environment factor (EEF). Our study clearly shows that molecular emission power spectra cannot be simply interpreted by the lineshape function (quantum dynamics of a molecular emitter), and the effect of the EEFs (photon propagation in a dielectric environment) has to be carefully considered. Place：S101, Gongquan Campuses, NTNU |
