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arXiv · 2212.10231

Ultra-Sensitive Extinction Measurements of Optically Active Defects in Monolayer MoS$_2$

Florian Sigger·Ines Amersdorffer·Alexander Hötger·Manuel Nutz·Jonas Kiemle·Takashi Taniguchi·Kenji Watanabe·Michael Förg·Jonathan Noe·Jonathan J. Finley·Alexander Högele·Alexander W. Holleitner·Thomas Hümmer·David Hunger·Christoph Kastl
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Abstract

We utilize cavity-enhanced extinction spectroscopy to directly quantify the optical absorption of defects in MoS$_2$ generated by helium ion bombardment. We achieve hyperspectral imaging of specific defect patterns with a detection limit below 0.01% extinction, corresponding to a detectable defect density below $10^{11}$ cm$^{-2}$. The corresponding spectra reveal a broad sub-gap absorption, being consistent with theoretical predictions related to sulfur vacancy-bound excitons in MoS$_2$. Our results highlight cavity-enhanced extinction spectroscopy as efficient means for the detection of optical transitions in nanoscale thin films with weak absorption, applicable to a broad range of materials.

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Florian Sigger, Ines Amersdorffer, Alexander Hötger, Manuel Nutz, Jonas Kiemle, Takashi Taniguchi, Kenji Watanabe, Michael Förg, Jonathan Noe, Jonathan J. Finley, Alexander Högele, Alexander W. Holleitner, Thomas Hümmer, David Hunger, Christoph Kastl. 2022-12-20. Ultra-Sensitive Extinction Measurements of Optically Active Defects in Monolayer MoS$_2$. https://doi.org/10.1021/acs.jpclett.2c02386

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