Nanoscale Surface Analysis of High Entropy Alloy

Hsin-Hui Huang; Meguya Ryu; Yoshiaki Nishijima; Haoran Mu; Mohit Kumar; Nguyen Hoai An Le; Adrian Cernescu; Jitraporn Vongsvivut; Andrew Siao Ming Ang; Lina Grineviciute; Challapalli Subrahmanyam; Junko Morikawa; Saulius Juodkazis

arXiv · 2603.26445

Nanoscale Surface Analysis of High Entropy Alloy

Hsin-Hui Huang·Meguya Ryu·Yoshiaki Nishijima·Haoran Mu·Mohit Kumar·Nguyen Hoai An Le·Adrian Cernescu·Jitraporn Vongsvivut·Andrew Siao Ming Ang·Lina Grineviciute·Challapalli Subrahmanyam·Junko Morikawa·Saulius Juodkazis

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Abstract

Nanoscale surface analysis of 1 micrometer thick high entropy alloys (HEAs) was carried out using nano-IR for hyperspectral imaging and single point spectroscopy in the 700-1700 1/cm spectral range. Nano-IR is based on the detection of scattered light from an oscillating metal coated nano-tip in one of the arms of the Fourier transform infrared spectrometer and has a resolution defined by the tip radius of the probe, 20 nm, regardless of the excitation wavelength. HEA CuPdAgPtAu showed an absorption and reflection increase at 900-1100 1/cm band, which is consistent with Drude-Lorenz modeling of permittivity, however, could also signify oxide formation as tested by X-ray photoelectron spectroscopy of CuPdAgPtAu and CrFeCoNiCuMo. Realization of polarization analysis for nano-IR nano-spectroscopy in the plane perpendicular to the sample's surface is discussed and modeled. The currently available modality of surface analysis with the excitation-detection mode of the p-pol. antenna can be extended to full 3D analysis of the orientational dependencies of local absorbance and refractive index.

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Hsin-Hui Huang, Meguya Ryu, Yoshiaki Nishijima, Haoran Mu, Mohit Kumar, Nguyen Hoai An Le, Adrian Cernescu, Jitraporn Vongsvivut, Andrew Siao Ming Ang, Lina Grineviciute, Challapalli Subrahmanyam, Junko Morikawa, Saulius Juodkazis. 2026-03-27. Nanoscale Surface Analysis of High Entropy Alloy. https://arxiv.org/abs/2603.26445

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