Imperial College London
Alternate

ProfessorRupertOulton

Faculty of Natural Sciences, Department of Physics

Professor of Nanophotonics
 
 
 
//

Contact

 

+44 (0)20 7594 7576r.oulton

 
 
//

Location

 

914Blackett LaboratorySouth Kensington Campus

//

Summary

 

Publications

Citation

BibTex format

@article{Fu:2022:rs.3.rs-1199041/v1,
author = {Fu, M and Mota, M and Xiao, X and Jacassi, A and Li, Y and Riaz, A and Maier, S and Oulton, R},
doi = {rs.3.rs-1199041/v1},
title = {Near unity Raman β-factor of surface enhanced Raman scattering in a waveguide},
url = {http://dx.doi.org/10.21203/rs.3.rs-1199041/v1},
year = {2022}
}
Download

RIS format (EndNote, RefMan)

TY  - JOUR
AB  - The Raman scattering of light by molecular vibrations offers a powerful technique to ‘fingerprint’ molecules via their internal bonds and symmetries. Since Raman scattering is weak 1 , methods to enhance, direct and harness it are highly desirable, e.g. through the use of optical cavities 2 , waveguides 3–6 , and surface enhanced Raman scattering (SERS) 7–9 . While SERS offers dramatic enhancements 6,15,22,2 by localizing light within vanishingly small ‘hot-spots’ in metallic nanostructures, these tiny interaction volumes are only sensitive to few molecules, yielding weak signals that are difficult to detect 10 . Here, we show that SERS from 4-Aminothiophenol (4-ATP) molecules bonded to a plasmonic gap waveguide is directed into a single mode with > 99% efficiency. Although sacrificing a confinement dimension, we find > 10 4 times SERS enhancement across a broad spectral range enabled by the waveguide’s larger sensing volume and non-resonant mode. Remarkably, the waveguide-SERS (W-SERS) is bright enough to image Raman transport across the waveguides exposing the roles of nanofocusing 11–13 and the Purcell effect 14 . Emulating the e-factor from laser physics 15–17 , the near unity Raman -factor observed exposes the SERS technique in a new light and points to alternative routes to controlling Raman scattering. The ability of W-SERS to direct Raman scattering is relevant to Raman sensors based on integrated photonics 7–9 with applications in gas and bio-sensing as well as healthcare.
AU  - Fu,M
AU  - Mota,M
AU  - Xiao,X
AU  - Jacassi,A
AU  - Li,Y
AU  - Riaz,A
AU  - Maier,S
AU  - Oulton,R
DO  - rs.3.rs-1199041/v1
PY  - 2022///
TI  - Near unity Raman β-factor of surface enhanced Raman scattering in a waveguide
UR  - http://dx.doi.org/10.21203/rs.3.rs-1199041/v1
ER  -
Download