Colloidal energy transfer systems for spaser based nanolasing

拟议的项目旨在开发能够在明确定义的波长范围内产生相干光子的胶体能量传递系统，这是一个快速发展的研究领域。该研究项目为产生相干光子的纳米光学元件的制备、表征和理论理解提供了重要贡献，为传感、亚衍射极限成像、超材料和全光计算等领域的潜在应用提供了可能。为此，我们将使用spaser效应（通过受激辐射的表面等离子体放大）并使用等离子体纳米结构来支持和集中强光频率场。与经典激光器类似，这样的spaser需要一个泵浦、一个谐振器和一个增益介质。实现基于spaser的纳米激光器的一个主要挑战是增益效率，因为增益的放大必须补偿光学损失以达到激光所需的临界阈值。我们计划通过使用低光学损耗等离子体纳米结构和明亮、光稳定的荧光团来提供足够的放大，从而提高增益效率。最重要的是，我们将系统地分析能量传递行为，以确定理想的荧光团负载密度和距离以及荧光团类型。近年来，在等离子体纳米材料的合成和功能化方面的研究活动非常活跃，这使得现在可以通过实验实现允许激光作用的能量转移胶体。此外，用于集合和单粒子测量的复杂光谱工具现在可用，并将允许实际识别spaser性能。本项目结合了胶体和聚合物化学、物理和理论模拟的元素。因此，在Emmy Noether计划框架下的拟议项目非常适合拜罗伊特大学的“大分子和胶体研究”研究背景，并受益于强大的科学环境。拜罗伊特大学是一个优秀的研究平台，在这里，初级科学家得到系统的支持，并找到理想的工作条件。优秀的实验室致力于纳米结构材料的合成，能够合成复杂的无机、有机和复合结构。此外，各种各样的仪器，重要的表征和处理胶体，是可用的。该项目完全符合化学学院物理化学一系（S. Förster教授）、物理化学二系（A. Fery教授）和实验物理四系（J. Köhler教授）的要求。对本项目具有特殊研究重点的机构，如“拜罗伊特研究中心<s:2> r Kolloide und Grenzflächen”（BZKG）和“拜罗伊特研究所<s:2> r makromolek<e:1> lforschung”（BIMF）都可以访问。此外，申请人的研究兴趣完全符合“Sonderforschungsbereich 840”（SFB 840）的主题。

The proposed project aims at the development of colloidal energy transfer systems capable of gener-ating coherent photons in a well-defined wavelength regime, which is a rapidly evolving field of re-search. This research project provides important contributions to the preparation, characterization and theoretical understanding of nanoscaled optical components generating coherent photons for possible applications in sensing, sub-diffraction limit imaging, metamaterials and all-optical computing. For this purpose, we will use the spaser effect (Surface Plasmon Amplification by Stimulated Emission of Radiation) and employ plasmonic nanostructures to support and concentrate strong optical-frequency fields. In analogy to a classical laser, such a spaser requires a pump, a resonator and a gain medium. A major challenge in the realization of spaser based nanolasers is the gain efficiency, since the amplification by gain has to compensate optical losses to reach the critical threshold needed for lasing. We plan to increase the gain efficiency by using low optical loss plasmonic nanostructures and bright, photostable fluorophores to provide sufficient amplification. Most importantly we will analyze the energy transfer behavior systematically to determine the ideal fluorophore loading density and distance as well as fluorophore type. The strong research activity with respect to the synthesis and functionalization of plasmonic nanomaterials in the last years makes it now possible to experimentally realize energy transfer colloids which allow for spaser action. Furthermore, sophisticated spectroscopy tools for ensemble and single particle measurements are now available and will allow the actual identification of spaser performance. The present project combines elements of colloid and polymer chemistry, physics and theoretical simulation. Consequently, the proposed project in the framework of the Emmy Noether programme fits well into the research profile “Macromolecular and Colloid Research” at the University of Bayreuth and benefits from the strong scientific environment. The University of Bayreuth represents an excellent research platform, where junior scientists are systematically supported and find ideal working conditions. Excellent laboratories dedicated to synthesis of nanostructured materials can be found enabling synthesis of complex inorganic, organic and composite structures. In addition, a broad variety of instruments, important for characterization and processing of colloids, is available. The proposed project fits perfectly into the school of chemistry with the departments Physical Chemistry I (Prof. S. Förster), Physical Chemistry II (Prof. A. Fery) and the department Experimental Physics IV (Prof. J. Köhler). Institutions with a special research focus important for the present project such as the „Bayreuther Zentrum für Kolloide und Grenzflächen“ (BZKG) and the „Bayreuther Institut für Makromolekülforschung“ (BIMF) are accessible. Furthermore, the proposer’s research interests fit perfectly into the theme of the „Sonderforschungsbereich 840” (SFB 840).