OP: Coherence and Energy Transfer Processes in Lattice Plasmon Lasers

非技术描述：激光在诸如蓝光光盘读卡器和超市条形码扫描仪等产品中无处不在。缩小激光器的尺寸将使其应用于令人兴奋的新领域，从超灵敏的微型传感器到更快的计算机芯片，再到宽带无线网络。然而，了解纳米级激光器如何工作和放大光仍然是一个挑战。鉴于纳米激光器的物理结构与传统激光器有很大的不同，本工作旨在揭示纳米激光器的基本工作原理。光学和光子学是美国国家科学基金会和美国的一项重大倡议，该项目的广泛影响集中于光和纳米光子学活动。例子包括通过撰写评论文章向公众介绍纳米光子学的想法，通过编辑角色为科学界服务，以及为当地高中学生和教师举办关于激光和其他光学现象的实践活动。最后，利用他们的编辑经验，项目负责人参加研讨会，重点关注出版和处理有争议的研究课题的伦理问题。技术描述：本项目涉及由金属纳米粒子阵列组成的纳米级激光器的相干性和能量转移过程机制的实验和理论研究，其中表面等离子激元激发驱动有机染料的受激辐射。到目前为止，对于染料分子如何在纳米水平上影响居群反转和在宏观水平上影响激光，只有粗略的了解。本研究旨在利用晶格等离子体作为模型光学反馈系统来解决纳米激光器中的这一知识缺口。与传统激光器不同，这里研究的腔结构中的损耗量化并不直接。该项目提出了一种新的方法来理解基于相干性、腔尺寸和超快特性的晶格等离子体激光器激光作用中的竞争能量转移过程。电动力学耦合密度矩阵方法用于模拟这些激光器中的相干效应。

Nontechnical description: Lasers are ubiquitous in products such as readers for Blu-ray discs and bar-code scanners at supermarkets. Shrinking the size of lasers will enable their use in exciting new applications, from ultra-sensitive miniature sensors to faster computer chips to broadband wireless networks. However, understanding how nanoscale-sized lasers operate and amplify light remains a challenge. This work aims to uncover the fundamental operational principles of nanoscale lasers, given that their physical structure is significantly different from that of traditional lasers. Optics and photonics is a major NSF and US initiative, and broader impacts of this project focus on light and nano-photonics activities. Examples include introducing ideas in nano-photonics to the public by writing opinion pieces, serving the scientific community through editorial roles, and hosting hands-on activities on lasers and other optical phenomena for local high school students and teachers. Finally, drawing upon their editorial experience, the project leaders participate in workshops that focus on ethics in publishing and handling of controversial research topics.Technical description: This project addresses experimental and theoretical studies of the mechanisms of coherence and energy transfer processes in nanoscale lasers comprising arrays of metal nanoparticles, in which surface plasmon excitations drive stimulated emission in organic dyes. To date, only a cursory understanding of how dye molecules affect population inversion at the nanoscopic level and lasing at the macroscopic level exists. This research aims to address this knowledge gap in nano-lasers using lattice plasmons as a model optical feedback system. Unlike in conventional lasers, quantification of loss in the cavity structures studied here is not straightforward. This project addresses a new approach to understanding competing energy transfer processes in the lasing action of lattice plasmon lasers based on coherence, cavity size, and ultra-fast characteristics. Electrodynamics coupled to density matrix methods serve to model coherence effects in these lasers.