title: Dimer-on-mirror SERS substrates with attogram sensitivity fabricated by colloidal lithography.
abstract: Nanoplasmonic substrates with optimized field-enhancement properties are a key component in the continued development of surface-enhanced Raman scattering (SERS) molecular analysis but are challenging to produce inexpensively in large scale. We used a facile and cost-effective bottom-up technique, colloidal hole-mask lithography, to produce macroscopic dimer-on-mirror gold nanostructures. The optimized structures exhibit excellent SERS performance, as exemplified by detection of 2.5 and 50 attograms of BPE, a common SERS probe, using Raman microscopy and a simple handheld device, respectively. The corresponding Raman enhancement factor is of the order 10(11), which compares favourably to previously reported record performance values.
authors.affiliation: Department of Applied Physics, Division of Bionanophotonics, Chalmers University of Technology, Gothenburg, Sweden. hakonen@chalmers.se kall@chalmers.se.
authors.forename: Aron
authors.initials: A
authors.lastname: Hakonen
authors.forename: Mikael
authors.initials: M
authors.lastname: Svedendahl
authors.forename: Robin
authors.initials: R
authors.lastname: Ogier
authors.forename: Zhong-Jian
authors.initials: ZJ
authors.lastname: Yang
authors.forename: Kristof
authors.initials: K
authors.lastname: Lodewijks
authors.forename: Ruggero
authors.initials: R
authors.lastname: Verre
authors.forename: Timur
authors.initials: T
authors.lastname: Shegai
authors.forename: Per Ola
authors.initials: PO
authors.lastname: Andersson
authors.forename: Mikael
authors.initials: M
authors.lastname: Käll