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

References in corpus (5)

• Measurement of the optical dielectric function of transition metal dichalcogenide monolayers: MoS2, MoSe2, WS2 and WSe2
• Irradiation of Nanostrained Monolayer WSe${}_2$ for Site-Controlled Single-Photon Emission up to 150 K
• Position-controlled quantum emitters with reproducible emission wavelength in hexagonal boron nitride
• Tunable magneto-optical properties in MoS${}_2$ via defect-induced exciton transitions
• Electron dynamics in a 2D nanobubble: A two-level system based on spatial density

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