Work

Visible and near-infrared nanoscale spectroscopy with photo-induced force microscopy

Year: 2024

Type: article

Abstract: Photo-induced force microscopy (PiFM) uses laser modulation at the atomic force microscope cantilever's typical mechanical resonance frequency, to encode the material near-field response in the probes nanomechanics. While this technique offers the simplicity gained by mechanical detection, it can be challenging for hyperspectral measurements. Modulation in the visible and near-infrared ranges, often involves using acousto-optic modulators that introduce a wavelength-dependent laser steering, detrimental for spectroscopic purposes. Here, we introduce an innovative strategy, based on an electro-optic modulator (EOM), which eliminates the need for realignment, making PiFM a valuable tool for nanoscale spectroscopy in the visible and near-infrared spectra. We test the new EOM-based setup on a WSe 2 sample where we visualize the propagation of polaritonic waveguide modes, which hybridize with the material exciton to form exciton-polaritons. Finally, we extend this EOM-based PiFM setup from standard amplitude-modulation PiFM to polarization-modulation PiFM, paving the way for investigations, at the nanoscale, of linear birefringence and dichroism in the visible and near-infrared ranges.

Source: Optics Express

DOI: 10.1364/oe.544845

Authors: Stefano Chiodini, Andrea Mancini, Giacomo Venturi, William L. Wilson, Antonio Ambrosio

Institution: Harvard University

Language: English

Topic: Force Microscopy Techniques and Applications

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,270

Funders: European Space Agency, H2020 European Research Council