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DOE OSTI · 2329513

Probing Local Optical Fields via Ultralow Frequency Raman Scattering from a Corrugated Probe

Wang, Chih-Feng·Mantilla, Alexander C.·Krayev, Andrey·Gu, Yi·El-Khoury, Patrick Z.
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Abstract

Here we revisit nanoscale local optical field imaging via tip-enhanced Raman scattering (TERS). Rather than taking advantage of molecular reporters to probe different aspects of the local fields, we show how ultralow frequency Raman (ULF) scattering from the (nano-corrugated) metallic probe itself can be used for the same purpose. The bright ULF-TERS response we record allows non-invasive (tapping mode feedback) local field imaging, enables visualizing the local fields of small (down to 20 nm) isolated plasmonic particles, and can also be exploited to distinguish between Si and SiO2 domains with 5 nm spatial resolution. We describe our approach and its limitations, particularly when it comes to using all-metallic vs molecular reporters.

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Wang, Chih-Feng, Mantilla, Alexander C., Krayev, Andrey, Gu, Yi, El-Khoury, Patrick Z.. 2023-09-12. Probing Local Optical Fields via Ultralow Frequency Raman Scattering from a Corrugated Probe. https://doi.org/10.1021/acs.jpclett.3c02122

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