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Updated: May 14, 2026

Characterization of Biological Absorption Spectra Spanning the Visible to the Short-Wave Infrared
Published on: January 10, 2025
Surface-enhanced infrared absorption using individual cross antennas tailored to chemical moieties
Lisa V Brown1, Ke Zhao, Nicholas King
1Department of Chemistry, Rice University, Houston, Texas 77005, United States.
Abstract:
The development of antenna structures for surface-enhanced infrared absorption spectroscopy (SEIRA) is a topic of intense and growing interest for extending IR spectroscopy to zeptomolar quantities and ultimately to the single-molecule level. Here we show that strong infrared spectroscopic enhancements can be obtained from individual gold nanoantennas using conventional IR spectrometric sources. The antenna structure dimensions can be tuned to enhance the IR modes of specific chemical moieties. Simulations of the electric field intensity in the antenna junction region reveal a maximum SEIRA enhancement factor of more than 12,000. These findings open new opportunities for analyzing IR vibrations of exceptionally small quantities of molecules using widely accessible light sources.
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