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arXiv · 2203.07025

Nanomechanical spectroscopy of 2D materials

Jan N. Kirchhof·Yuefeng Yu·Gabriel Antheaume·Georgy Gordeev·Denis Yagodkin·Peter Elliott·Daniel B. de Araújo·Sangeeta Sharma·Stephanie Reich·Kirill I. Bolotin
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Abstract

We introduce a nanomechanical platform for fast and sensitive measurements of the spectrally-resolved optical dielectric function of 2D materials. At the heart of our approach is a suspended 2D material integrated into a nanomechanical resonator illuminated by a wavelength-tunable laser source. From the heating-related frequency shift of the resonator as well as its optical reflection measured as a function of photon energy, we obtain the real and imaginary parts of the dielectric function. Our measurements are unaffected by substrate-related screening and do not require any assumptions on the underling optical constants. This fast ($τ_{rise}$ $\sim$ 135 ns), sensitive (noise-equivalent power = 90 $\frac{pW}{\sqrt{Hz}}$ ), and broadband (1.2 $-$ 3.1 eV, extendable to UV-THz) method provides an attractive alternative to spectroscopic or ellipsometric characterisation techniques.

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Jan N. Kirchhof, Yuefeng Yu, Gabriel Antheaume, Georgy Gordeev, Denis Yagodkin, Peter Elliott, Daniel B. de Araújo, Sangeeta Sharma, Stephanie Reich, Kirill I. Bolotin. 2022-09-26. Nanomechanical spectroscopy of 2D materials. https://doi.org/10.1021/acs.nanolett.2c01289

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