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arXiv · 2408.11534

Double tips for in-plane polarized near-field microscopy and spectroscopy

Patryk Kusch·Jose Pareja Arcos·Aleksei Tsarapkin·Victor Deinhart·Karsten Harbauer·Katja Höflich·Stephanie Reich
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Abstract

Near-field optical microscopy and spectroscopy provide high-resolution imaging below the diffraction limit, crucial in physics, chemistry, and biology for studying molecules, nanoparticles, and viruses. These techniques use a sharp metallic tip of an atomic force microscope (AFM) to enhance incoming and scattered light by excited near-fields at the tip apex leading to high sensitivity and a spatial resolution of a few nanometers. However, this restricts the near-field orientation to out-of-plane polarization, limiting optical polarization choices. We introduce double tips that offer in-plane polarization for enhanced imaging and spectroscopy. These double tips provide superior enhancement over single tips, although with a slightly lower spatial resolution (~30nm). They enable advanced studies of nanotubes, graphene defects, and transition metal dichalcogenides, benefiting from polarization control. The double tips allow varied polarization in tip-enhanced Raman scattering and selective excitation of transverse-electric and -magnetic polaritons, expanding the range of nanoscale samples that can be studied.

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Patryk Kusch, Jose Pareja Arcos, Aleksei Tsarapkin, Victor Deinhart, Karsten Harbauer, Katja Höflich, Stephanie Reich. 2024-08-21. Double tips for in-plane polarized near-field microscopy and spectroscopy. https://arxiv.org/abs/2408.11534

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