Electromigrated nanoscale gaps for surface-enhanced Raman spectroscopy

Abstract

Single-molecule detection with chemical specificity is a powerful and much desired tool for biology, chemistry, physics, and sensing technologies. Surface-enhanced spectroscopies enable single molecule studies, yet reliable substrates of adequate sensitivity are in short supply. We present a simple, scaleable substrate for surface-enhanced Raman spectroscopy (SERS) incorporating nanometer-scale electromigrated gaps between extended electrodes. Molecules in the nanogap active regions exhibit hallmarks of very high Raman sensitivity, including blinking and spectral diffusion. Electrodynamic simulations show plasmonic focusing, giving electromagnetic enhancements approaching those needed for single-molecule SERS.

29 pages, 11 figures (includes supp. material)

References in corpus (2)

• Controlled Fabrication of Nanogaps in Ambient Environment for Molecular Electronics
• The role of Joule heating in the formation of nanogaps by electromigration

Cited by in corpus (22)

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• Simultaneous measurements of electronic conduction and Raman response in molecular junctions
• Vibrational and electronic heating in nanoscale junctions
• Nanogap-Enhanced Infrared Spectroscopy with Template-Stripped Wafer-Scale Arrays of Buried Plasmonic Cavities
• Current-induced atomic dynamics, instabilities, and Raman signals: Quasi-classical Langevin equation approach
• Dark plasmons in hot spot generation and polarization in interelectrode nanoscale junctions
• Voltage tuning of vibrational mode energies in single-molecule junctions
• Spectrally and Spatially Configurable Superlenses for Optoplasmonic Nanocircuits
• Raman scattering in current carrying molecular junctions. A preliminary account
• Field enhancement in subnanometer metallic gaps
• Electronic and optical properties of electromigrated molecular junctions
• Linear optical response of current-carrying molecular junction: A NEGF-TDDFT approach
• Photonics and Spectroscopy in Nanojunctions: A Theoretical Insight
• Interplay of bias-driven charging and the vibrational Stark effect in molecular junctions
• Light-induced current in molecular junctions: Local field and non-Markov effects
• Topology Optimization of Surface-enhanced Raman Scattering Substrates
• Hubbard NEGF Analysis of Photocurrent in Nitroazobenzene Molecular Junction
• Plasmon-assisted photoresponse in Ge-coated bowtie nanojunctions
• Quantifying efficiency of remote excitation for surface enhanced Raman spectroscopy in molecular junctions
• Light Emission and Conductance Fluctuations in Electrically Driven and Plasmonically Enhanced Molecular Junctions
• Plasmons in nanoscale metal junctions: optical rectification and thermometry
• Color Tuning by Spontaneous Propagation of Gap Surface Plasmons in Epsilon Near Zero Nano-Cavity