期刊
NANO LETTERS
卷 12, 期 10, 页码 5239-5244出版社
AMER CHEMICAL SOC
DOI: 10.1021/nl302418n
关键词
Energy-filtering TEM; 3D finite-difference time-domain; toroidal eigenmodes; oligomers; plasmonics; nanocavities
类别
资金
- Alexander-von-Humboldt foundation
Plasmonics has become one of the most vibrant areas in research with technological innovations impacting fields from telecommunications to medicine. Many fascinating applications of plasmonic nanostructures employ electric dipole and higher-order multipole resonances. Also magnetic multipole resonances are recognized for their unique properties. Besides these multipolar modes that easily radiate into free space, other types of electromagnetic resonances exist, so-called toroidal eigenmodes, which have been largely overlooked historically. They are strongly bound to material structures and their peculiar spatial structure renders them practically invisible to conventional optical microscopy techniques. In this Letter, we demonstrate toroidal modes in a metal ring formed by an oligomer of holes. Combined energy-filtering transmission electron microscopy and three-dimensional finite difference time domain analysis reveal their distinct features. For the study of these modes that cannot be excited by optical far-field spectroscopy, energy-filtering transmission electron microscopy emerges as the method of choice. Toroidal moments bear great potential for novel applications, for example, in the engineering of Purcell factors of quantum-optical emitters inside toroidal cavities.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据