标题： C60薄膜中晶界处的激子淬灭 显示英文标题

标题： Quenching of excitons at grain boundaries in C60 thin films

摘要： 激子寿命在有机光电设备的性能中起着关键作用。 在本研究中，我们利用时间分辨和角度分辨光电子能谱（TR-ARPES）研究了多个旋转畴的存在，以及因此产生的晶界，如何影响C60/Au(111)薄膜中的激子动力学。 我们发现，具有多个旋转畴的薄膜表现出较短的激子寿命，并且有激子-激子湮灭的证据，即使在一个畴占主导地位的情况下也是如此。 扫描隧道显微镜（STM）测量显示，在晶界处局部介电常数降低导致了电子结构的变化，通过激子聚焦和其他额外衰减通道提供了寿命减少的机制。 这些发现突显了薄膜质量在决定固有激子寿命中的关键作用，并表明通过集合测量几乎无法检测到的微量无序也可以显著影响动力学。 这些结果意味着精确的结构控制对于优化有机光电设备的性能至关重要。 显示英文摘要

摘要： Exciton lifetimes play a critical role in the performance of organic optoelectronic devices. In this work, we investigate how the presence of multiple rotational domains, and therefore grain boundaries, impacts exciton dynamics in thin films of C60/Au(111) using time and angle-resolved photoemission spectroscopy (TR-ARPES). We find that films with multiple rotational domains exhibit shorter exciton lifetimes and evidence of exciton-exciton annihilation, even when one domain predominates. Scanning tunneling microscopy (STM) measurements reveal electronic structure changes resulting from a locally reduced dielectric constant at grain boundaries, providing a mechanism for lifetime reduction through exciton funneling and other additional decay channels. These findings highlight the critical role of film quality in determining intrinsic exciton lifetimes, and show that minuscule amounts of disorder that are nearly undetectable by ensemble measurements can significantly impact dynamics. These results imply that precise structural control is essential for optimize the performance of organic optoelectronic devices.