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

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.

17 pages main manuscript, 7 pages supporting information

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Cited by in corpus (2)

• Creation and Microscopic Origins of Single-Photon Emitters in Transition Metal Dichalcogenides and Hexagonal Boron Nitride
• Reduced absorption due to defect-localized interlayer excitons in transition metal dichalcogenide-graphene heterostructures