  Hotspots of surface-enhanced resonance Raman scattering (SERRS) are localized
within 1 nm at gaps or crevices of plasmonic nanoparticle (NP) dimers. We
demonstrate SERRS hotspots with volumes that are extended in one dimension tens
of thousand times compared to standard zero-dimensional hotspots using gaps or
crevices of plasmonic nanowire (NW) dimers.
