Surface enhanced Raman spectroscopy using 2D plasmons of InN nanostructures

Abstract

We explored the surface enhanced Raman scattering (SERS) activity of the InN nanostructures, possessing surface electron accumulation (SEA), using the Rhodamine 6G (R6G) molecules. SERS enhancement is observed for the InN nanostructures which possess surface electron accumulation (SEA). In case of high temperature grown InN samples, a peak is observed in the low wave number (THz region) of Raman spectra of InN nanostructures originating from excitation of the two dimensional (2D) plasmons of the SEA. The enhancement factor of four orders was calculated with the assumption of monolayer coverage of analyte molecule. SERS enhancement of InN nanostructures is attributed to the 2D plasmonic nature of InN nanostructures invoking SEA, rather than the contributions from 3D surface plasmon resonance (SPR) and chemical interaction. The role of 2D plasmon excitation in SERS enhancement is corroborated by the near-field light-matter interaction studies using near-field scanning optical microscopy.

arXiv comment25 pages,6 figures, supplementary file included

References in corpus (5)

• Fano resonances in nanoscale structures
• Observation and analysis of Fano-like lineshapes in the Raman spectra of molecules adsorbed at metal interfaces
• Terahertz radiation due to random grating coupled surface plasmon polaritons
• Excitation dependent Raman studies of self-seeded grown InN nanoparticles with different carrier concentration
• Effect of Scattering Efficiency in the Tip Enhanced Raman Spectroscopic Imaging of Nanostructures in the Sub Diffraction Limit