LSPs——large EM field ↑——apply
LSPR——dielectric environment——sensing techniques
The electrons are free to move in one or two dimensions, thus SPPs
can be excited and propagate along the metal/dielectric interface.
NWs/NWs
2、Coupled medal NPs
NPs dimers and “hot spots”
The influencing factors of the near field coupling
1、Angle——the incident electric field∥the axis （Max） 2、 Gap——gap↓——energy↓——resonance peak
Heterodimer——novel optical properties ———Fano resonance.
EM coupling（ non-spherical ）—— relative orientation.
The nanogaps which strongly confine induced EM fields are supreme systems for SERS applications
等离子体（成分的
物质形态，广泛存在于宇宙中，常被视为是物质的第四态，被称为等离 子态，或者“超气态”，也称“电浆体”。
等离子体的特性
1、具有很高的电导率，和电磁场的耦合作用也极强 2、和一般气体不同，包含两到三种不同的组成粒子，且组成粒子间的相互 作用较大 3、速率分布可能偏离麦克斯韦分布 4、具有表面等离效应
Based on the SPs interference principle, a complete set of plamonic logic gates and other functional devices can be realized by designing different NW networks
LSPR is altered
the interaction —— the distance
The EM coupling between the NP and the image particle produce large field enhancement in the gap between the NP and the film
nanohole NPs arrays
single molecule SERS
plasmonic antennas
nanohole/NP pairs plasmonic tweezers nanocube dimers quantum plasmonics nanorod dimers nonlinear plasmonics
SPP characteristics in metal NWs
Applications
4、NWs network structures
4.1 SPP routing in branched NWs
4.2 SPP interference in complex NWs network
1、The thickness of the film is much larger than the diameter of the NP 2、The film can then be treated as a mirror
3.2 Coupled NPs/NWs
Characteristic of NWs
6 Conclusion
In complex metal nanostructures, the SPs in each single component interact with that in the others, for example, LSPs in a single NP can couple to that in another one or to SPPs in a NW or metal film,resulting in extra EM enhancement at the nanogaps. SPPs in different NWs can interfere with each other, making possible selective routing of propagating SPPs to desired output terminals. The complex EM interactions give rise to more flexibility in tailoring the SPs for advanced applications, such as remote SERS sensing and plasmonic logic gates. The dielectric substrate or surface coating is another critical parameter that affects the SPs properties, including the LSPR and the SPPs wavelength and propagation length. In fact, this effect provides an alternative method to tailor the SPs characteristics for particular applications.
the plasmonic properties of several typical types of complex metal nanostructures
electromagnetically coupled nanoparticles NPs/metal films NPs/nanowires (NWs)
报告人：
Content
1、introduction of plasma
2、coupled metal NPs 3、coupled NPs/metal film and NPs/NWs 4、NWs network structures 5、Conclusion
1、 introduction of plasma
等离子体的应用：工业、农业、环保、军事、宇航、能源、天体等方面
In metal nanoparticles , the collective oscillations of free electrons
are confined in all three-dimensions, resulting in the reputed localized surface plasmons (LSPs).
3、Coupled NPs/metal film and NPs/NWs
3.1 NP over metal film (NPOF)
A dipole ——an image dipole （ incident electric field
⊥surface）
The system: the NP →the image