以宏觀量子電動力學觀點探討輻射和非輻射過程的統一理論

Abstract

隨著有機光電技術的應用日漸廣泛，如何設計具備高亮度和高效率的有機光電裝置成為科學界關注的焦點。其中，輻射與非輻射過程的相互競爭扮演著至關重要的角色。本論文將以理論角度切入，試圖探討在不依賴分子設計的情況下，複雜介電環境如何影響輻射與非輻射過程的速率。本論文將涵蓋兩個主要部份: 第一部分在宏觀量子電動力學 (macroscopic quantum electrodynamics) 的理論框架下，利用一般性波恩-黃展開 (generalized Born-Huang expansion) 的理論方法描述電子、原子核、電磁極化子 (polariton) 三者交互作用的系統，並得到作為輻射與非輻射過程驅動力的非絕熱耦合 (non-adiabatic coupling)；第二部分建立輻射和非輻射過程的統一理論，闡述不同的介電環境對其速率的影響，並發現了輻射和非輻射途徑交互作用下所產生的新躍遷過程。我們相信這些理論發現能為有機光電材料設計開拓利用分子與周遭環境交互作用的新研究方向。

The interplay between radiative and non-radiative processes is one of the crucial issues in designing bright and efficient organic photoelectric devices. Approaching the topic from a theoretical perspective, this thesis explores how radiative and non-radiative processes can be manipulated through complex dielectric environments without explicit molecular design. The thesis is divided into two main parts. The first part focuses on developing the generalized Born-Huang expansion within the macroscopic quantum electrodynamics framework to describe the coupled nucleus–electron–polariton system. We obtain the non-adiabatic couplings that serves as the driving force for both radiative and non-radiative processes. The second part establishes a unified theory comprising radiative and non-radiative rates, elucidating the effect of diverse dielectric environments on rate modification. Additionally, the theory uncovers new processes resulting from the interference between radiative and non-radiative pathways. We believe these findings pave the way for designing materials with desirable optical properties by utilizing the interaction between molecules and the surrounding media.