期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：2016
卷号：113
期号：50
页码：14201-14206
DOI：10.1073/pnas.1615281113
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：SignificancePlasmonic nanostructures that can amplify localized optical fields and support ultranarrow resonances are critical for applications ranging from ultrasensitive molecular sensing to nanoscale lasing. However, the active engineering and maintaining of narrow resonances over a broad range of wavelengths, within a single system, is a grand challenge. In this paper, we introduce a platform that can overcome the limitations of as-fabricated nanoparticle arrays as well as toggle between different lattice plasmon mode orders (dipolar or quadrupolar) by mechanical manipulation of the sample along different symmetry directions. Dynamic tuning of narrow lattice plasmons (<5 nm) was possible over the entire visible wavelength range, which now opens possibilities in real-time optical systems and flexible electronics. Plasmonic nanostructures with enhanced localized optical fields as well as narrow linewidths have driven advances in numerous applications. However, the active engineering of ultranarrow resonances across the visible regime--and within a single system--has not yet been demonstrated. This paper describes how aluminum nanoparticle arrays embedded in an elastomeric slab may exhibit high-quality resonances with linewidths as narrow as 3 nm at wavelengths not accessible by conventional plasmonic materials. We exploited stretching to improve and tune simultaneously the optical response of as-fabricated nanoparticle arrays by shifting the diffraction mode relative to single-particle dipolar or quadrupolar resonances. This dynamic modulation of particle-particle spacing enabled either dipolar or quadrupolar lattice modes to be selectively accessed and individually optimized. Programmable plasmon modes offer a robust way to achieve real-time tunable materials for plasmon-enhanced molecular sensing and plasmonic nanolasers and opens new possibilities for integrating with flexible electronics.
