Presentation Information

[22a-A309-6]Electromagnetic enhancement by dipole-quadrupole coupled plasmon resonance through one dimensional hotspots of silver nanowire dimer junctions

〇Tamitake Itoh1, Yuko S. Yamamoto2 (1.AIST, 2.JAIST)

Keywords:

plasmon resonance,surface enhanced Raman scattering,silver nanowire

The interaction between the enhanced electric field localized and the molecular polarization in the gap between the dimers of gold and silver nanowires (NWs) generates the enhanced electric field region (hot spot HSs). The HSs, which is localized within several nanometers in the case of the gaps of nanoparticle (NP) dimers, are expanded one dimensionally (1D) by 10^4 times for NW dimers. This 1D HS can be applied to various cavity electromagnetic phenomena such as surface-enhanced Raman scattering (SERS) and ultrafast fluorescence. Recently, we investigated the contribution of the sub-radiant plasmon resonance to the enhanced electric field inside HSs of NP dimers. We found that, for NW dimers, it is also necessary to evaluate the enhancement spectra of SERS by sub-radiant plasmon resonance instead of radiative plasmon resonance when the diameter of nanowire is large or when there is asymmetry.