Ultra-Sensitive Extinction Measurements of Optically Active Defects in Monolayer MoS2

Sigger, Florian; Amersdorffer, Ines; Hoetger, Alexander; Nutz, Manuel; Kiemle, Jonas; Taniguchi, Takashi; Watanabe, Kenji; Foerg, Michael; Noe, Jonathan; Finley, Jonathan J.; Hoegele, Alexander; Holleitner, Alexander W.; Huemmer, Thomas; Hunger, David and Kastl, Christoph (2022): Ultra-Sensitive Extinction Measurements of Optically Active Defects in Monolayer MoS2. In: Journal of Physical Chemistry Letters: pp. 10291-10296

Abstract

We utilize cavity-enhanced extinction spectroscopy to directly quantify the optical absorption of defects in MoS2 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 1 x 10(11) cm(-2). The corresponding spectra reveal a broad subgap absorption, being consistent with theoretical predictions related to sulfur vacancy-bound excitons in MoS2. 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.

• Item Type: Journal article
• Faculties: Physics
• Subjects: 500 Science > 530 Physics
• ISSN: 1948-7185
• Language: English
• DFG: Gefördert durch die Deutsche Forschungsgemeinschaft (DFG) - 390776260
• DFG: Gefördert durch die Deutsche Forschungsgemeinschaft (DFG) - 390814868
• DFG: Gefördert durch die Deutsche Forschungsgemeinschaft (DFG) - 422707584