Waveguide-enhanced Raman spectroscopy

Waveguide-enhanced Raman spectroscopy (WERS) exploits the electromagnetic enhancement that can be achieved at the surface of suitably designed waveguides to enhance the intensity of the Raman spectra of molecules close to the waveguide surface. This Primer describes practical aspects of WERS implementation including the choice of laser, choice of waveguide material, design and fabrication of the waveguides, coupling of light into and collection of light from the waveguide, and choice of spectrometer and filters. The methods for data collection and quantitative analysis of waveguide-enhanced Raman spectra are also described, together with the applications of WERS to problems in chemistry, materials science and bioscience. Issues of spectral reproducibility and key optimization factors are discussed together with a summary of technical limitations, current challenges and perspectives for future research. In many cases the material presented is supported by further, more detailed, discussion in the accompanying Supplementary Information.